CN116288803A - A kind of anti-lodging PBT/PA12 sharpened toothbrush wire and its preparation method - Google Patents

Abstract

The invention discloses a lodging-resistant PBT/PA12 sharpening toothbrush wire and a preparation method thereof. The raw materials include the following components in parts by weight: 60-90 parts of polybutylene terephthalate (PBT), 10-40 parts of nylon 12 (PA12), 1-5 parts of amphiphilic block copolymer, anti- Oxygen agent 0.1-0.5 parts, lubricant 0.1-0.5 parts. The amphiphilic block copolymer used in the present invention is a block copolymer generated by amidation reaction between a dicarboxyl-terminated polybutylene terephthalate oligomer and a diamino-terminated nylon 12 oligomer. The amphiphilic block copolymer can effectively improve the compatibility of PBT and PA12, and realize the submicron size dispersion of PA12 dispersed phase in PBT matrix. A lodging-resistant PBT/PA12 sharpened toothbrush filament was prepared from the blend by melt spinning and cake sharpening.

Description

A kind of anti-lodging PBT/PA12 sharpened toothbrush wire and its preparation method

technical field

The invention relates to the field of brush filaments, in particular to a lodging-resistant PBT/PA12 sharpening toothbrush filament.

Background technique

Toothbrush is an indispensable tool for brushing teeth in people's daily life. The quality of toothbrush mainly depends on the quality of brush filaments. At present, toothbrush filaments mainly include polyester filaments and nylon filaments. Polyester filaments are mainly PBT filaments. Compared with nylon filaments, the biggest advantage of PBT filaments is that they can be chemically sharpened (NaOH solution is used as chemical sharpening liquid). The fiber is conical. After making a toothbrush, the head is relatively soft, causing less damage to the gums and can penetrate deep into the gap between the teeth. Compared with the flat toothbrush filament, it has a better cleaning effect. However, the poor lodging resistance of polyester filament restricts it. Promote it further. Nylon toothbrush filament has better flexibility and lodging resistance than PBT filament, but due to the superior solvent resistance of nylon material, it cannot be sharpened by traditional chemical sharpening method (using NaOH solution as chemical sharpening liquid) Some manufacturers use mechanical sharpening method to prepare nylon sharpened wire, but the cost is high, the efficiency is low, and the appearance and shape of the product cannot meet the needs of consumers. Therefore, preparing a toothbrush filament that is resistant to lodging and can be sharpened has always been a goal pursued by researchers.

Blending modification is a common method to balance the properties of polymer materials. Blending nylon materials with excellent lodging resistance and PBT to prepare toothbrush filaments is expected to improve the lodging resistance of PBT brush filaments while retaining its chemical sharpening advantages. However, nylon and PBT are two thermodynamically incompatible polymers. Under the conventional blending method, the nylon dispersed phase will be dispersed in the PBT matrix with a size of several microns or even tens of microns, and the large-sized nylon dispersed phase will become a stress. The defect points lead to the deterioration of the properties of the blends, and the optimization of the properties of the blends can only be achieved when the nylon dispersed phase is dispersed in submicron (0.1-1 μm) size.

Nylon 12 is a long-chain nylon material prepared by ring-opening polymerization of laurolactam. Compared with nylon 610 and nylon 612, it has excellent flexibility, lower water absorption and comparable lodging resistance, and can be applied to PBT Preparation of anti-lodging sharpened wire by modification.

Patent CN101724257A adopts a hyperbranched polyethyleneimine grafted nylon as a solubilizer to prepare nylon polyester blends, and utilizes a large number of terminal amino groups of polyethyleneimine to react with carboxyl groups in nylon and polyester in solution to obtain poly Terpolymer of ethyleneimine-co-nylon-co-polyester. The disadvantage is that it is necessary to use a solvent to make the three into a solution first, and an amidation reaction occurs at a high temperature. A large number of terminal amino groups of hyperbranched polyethyleneimine are prone to cross-linking reactions during the amidation reaction, and it is difficult to control the reaction end point. Terpolymers containing a large number of amide groups will lead to poor water resistance and chemical resistance.

Patent CN102660019B adopts solution polymerization to prepare high-temperature-resistant nylon/PBT/PET copolymer, and adds PBT, PET and aliphatic diamine to the solvent to undergo copolymerization reaction. Its reaction requires higher temperature and the solvent cannot be recovered, so it is difficult to realize industrial promotion.

Patent CN113773508B adopts sulfonic acid group grafting modified polyester as a solubilizer, and the sulfonic acid group reacts chemically with nylon amide group to obtain inner compatibilizing segment, which solves the compatibility problem of polyester/nylon composite material. The method lies in that the acquisition of the sulfonic acid group graft modified polyester and the reaction degree of the reaction between the sulfonic acid group and the amide group in the screw cannot be controlled.

Contents of the invention

The purpose of the present invention is to prepare a kind of anti-lodging PBT/PA12 sharpened toothbrush filament. .

The main technical problem faced by the present invention is to realize the submicron size dispersion of the nylon 12 dispersed phase in the PBT matrix.

In order to solve the above-mentioned technical problems, the technical principle adopted in the present invention is: using the principle of "similar compatibility", polymers with similar chemical structures have better compatibility. The main technical problem of the present invention turns into preparing a kind of polymer with structure close to nylon 12 and PBT, and this polymer has good compatibility with nylon 12 and PBT. Using the amidation reaction mechanism, the dicarboxyl-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer are amidated to prepare a block copolymer of PBT and nylon 12, which can effectively improve the PBT Compatibility with nylon 12 is expected to make nylon 12 dispersed in PBT matrix with submicron size to improve lodging resistance. In addition, by controlling the blending ratio of PBT and nylon 12, nylon 12 is dispersed in the "sea phase" PBT in the "island phase" without changing the chemical sharpening performance of the blend to prepare brush filaments, thereby preparing a lodging resistance PBT/PA12 sharpened toothbrush filament.

Therefore, in order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A kind of anti-lodging PBT/PA12 sharpening toothbrush filament, by weight, the raw material comprises the following components:

In some examples, preferably, the relative viscosity of the PBT is 0.6-0.85 (phenol-1,1,2,2-tetrachloroethane=1:1 (w/w) as solvent, 0.005g/ml concentration) , more preferably 0.75.

In some examples, preferably, the relative viscosity of the nylon 12 is 1.60-1.90 (m-cresol is the solvent, the concentration is 0.005 g/ml), more preferably 1.80.

In some examples, the antioxidant is a heat-resistant antioxidant selected from one or more of antioxidant 1010, antioxidant 1098, antioxidant 168, and antioxidant H10, preferably antioxidant Antioxidant 1010 and antioxidant 1681:1 quality compound system.

In some examples, the lubricant is selected from one or more of ethylene bis stearic acid amide (EBS), oleic acid amide, silicone oil, and paraffin, preferably ethylene bis stearic acid amide (EBS).

In some examples, the amphiphilic block copolymer is a block copolymer generated by amidation reaction between a dicarboxyl-terminated PBT oligomer and a diamino-terminated nylon 12 oligomer, and its preparation method includes the following steps :

(1) Preparation of double carboxyl-terminated PBT oligomers:

(1-1) Under an inert gas atmosphere, terephthalic acid (PTA), 1,4-butanediol (BDO) and catalyst 1 are kept at 220-240°C for 1-3h for esterification reaction; keep at 220-240°C , nitrogen purging for 0.5-1h for prepolymerization;

(1-2) After the prepolymerization is completed, add catalyst 2, and react for 0.5-2h at 240-250°C and absolute pressure below 100Pa; stop vacuuming, add inert gas to 50-100kPa, and cool the high-temperature melt with water cooling, drying, and crushing to prepare dicarboxy-terminated PBT oligomers.

Preferably, the catalyst 1 and the catalyst 2 are independently selected from one or more of tetrabutyl titanate, tetraisopropyl titanate, and dioctyltin oxide, preferably dioctyltin oxide.

Preferably, the amount of catalyst 1 added is 0.5-2‰ of the mass of terephthalic acid.

Preferably, the amount of catalyst 2 added is 1-3‰ of the mass of terephthalic acid.

Preferably, the number-average molecular weight of the prepared dicarboxyl-terminated PBT oligomer is 1000-3000, and the number-average molecular weight is regulated by the feeding ratio of terephthalic acid and butanediol.

Preferably, the carboxyl group content of the dicarboxyl-terminated PBT oligomer is 0.65-2.0 mmol/g.

(2) Preparation of diamino-terminated nylon 12 oligomer:

(2-1) Under an inert gas atmosphere, keep laurolactam, diamine-type end-capping agent and water at 270-290°C for 3-7h, preferably 5h to complete the ring-opening reaction of laurolactam;

(2-2) After the ring opening is completed, release the pressure to normal pressure, and reduce the temperature to 180-220°C at the same time, and then vacuumize for 30-60 minutes to complete the melting polycondensation; after the melting polycondensation is completed, stop vacuuming and protect the .

Preferably, the prepared nylon 12 oligomer has a number average molecular weight of 1000-3000.

Preferably, the bisamine-based end-capping agent is one or more of hexamethylenediamine, decanediamine, and dodecanediamine, more preferably dodecanediamine, and the amount added is determined by the number of nylon 12 oligomers Depends on the average molecular weight.

Preferably, the amount of water added is 8-18% of the mass of laurolactam, more preferably 12%.

Preferably, the amino group content of the nylon 12 oligomer is 0.65-2.0 mmol/g.

(3) Preparation of amphiphilic block copolymer:

Under an inert gas atmosphere, react diamino-terminated nylon 12 oligomers, dicarboxy-terminated PBT oligomers and molecular weight regulators at 240-250°C and an absolute pressure of 1kPa or less for 30-60 minutes to make dicarboxy-terminated PBT low The polymer undergoes amidation reaction with the diamino-terminated nylon 12 oligomer to obtain a block copolymer of PBT and PA12, which is drawn, water-cooled, pelletized, and dried to obtain amphiphilic block copolymer pellets.

In the step (3), the ratio of the number of moles of carboxyl groups of the dicarboxy-terminated PBT oligomer to the number of moles of amino groups of the diamino-terminated nylon 12 oligomer is 1:1.

The number average molecular weight of the amphiphilic block copolymer is 10000-30000, preferably 20000.

Preferably, the molecular weight regulator is selected from one of adipic acid, sebacic acid, dodecanedioic acid, benzoic acid, and lauric acid, preferably adipic acid, and the addition amount is determined by the amphiphilic block copolymer number average Depends on the molecular weight.

In some examples, the preparation method of the anti-lodging PBT/PA12 sharpened toothbrush wire of the present invention comprises the following steps:

(a) Preparation steps of PBT/PA12 mixed granules: add polybutylene terephthalate, nylon 12, amphiphilic block copolymer, lubricant, and antioxidant into a high-speed mixer and mix for 10-20 minutes to prepare The mixed ingredients are obtained, and then the mixed ingredients are melt-blended and extruded by a twin-screw extruder, water-cooled, pelletized, and dried to prepare PBT/PA12 mixed granules;

(b) silk cake preparation step: the silk cake is prepared by a melt spinning production line, the compounded pellets prepared in step (a) are plasticized by a single-screw extruder, extruded through a spinneret, water-cooled for setting, and thermally stretched. Winding and rewinding, heat treatment and hardening, packaging and cutting to prepare silk cakes;

(c) Silk cake sharpening treatment step: the silk cake prepared in step (b) is placed in a silk cake sharpening tank filled with sharpening liquid for sharpening treatment, cleaned, and dried to prepare sharpened toothbrush filaments.

In some examples, the aspect ratio of the twin-screw extruder used in the step (a) is 40-45, the screw speed is 100-200 rpm, and the temperature from the feeding section to the head is set at 180-250°C.

In some examples, the PA12 in the PBT/PA12 compounded granules is dispersed in the "sea phase" PBT matrix as an "island phase"; the size of the dispersed phase of the PA12 "island phase" is at the submicron level.

In some examples, the aspect ratio of the single-screw extruder used in the step (b) is 25-30, the rotation speed is 100-200 rpm, and the temperature from the feeding section to the head is set at 200-280°C.

In some examples, in the step (b), the thermal stretching is carried out in a hot oven at 130-160°C, preferably 140°C; the draw ratio is 3-6, preferably 4; the monofilament after thermal stretching The diameter is 6-8 mil, preferably 7 mil.

In some examples, in the step (b), the tow is heat-treated and hardened in a nitrogen-filled oven. The temperature of the nitrogen-filled oven is 100-130° C., preferably 120° C., and the treatment time is 1-3 hours, preferably 2 hours.

In some examples, the bundle of silk cakes cut in step (b) has a diameter of 50±2mm and a height of 30±2mm.

In some examples, the sharpening liquid used in the step (c) is NaOH aqueous solution, the concentration is 30-50wt%, preferably 40wt%; the treatment temperature is 100-140°C, preferably 120°C; the treatment time is 40-80min , preferably 60min.

In some examples, in the step (c), after the silk cake is sharpened, the silk cake needs to be washed with water until it becomes neutral (pH=7), and then dried in a vacuum oven at 80-100°C for 10-12 hours to obtain the finished product Sharpen the toothbrush filaments.

Compared with the prior art, the advantage of the present invention mainly lies in: the present invention utilizes the amidation reaction mechanism to carry out the amidation reaction between the PBT oligomer terminated by two carboxyl groups and the nylon 12 oligomer terminated by two amino groups, and prepare a kind of PBT and Nylon 12 block copolymer. When the block copolymer is used as a compatibilizer for melt blending of PBT and nylon 12, the block copolymer can effectively improve the compatibility of PBT and nylon 12, and can make nylon 12 disperse in the PBT matrix with submicron size, Nylon 12 with submicron size dispersion can improve the lodging resistance of PBT wire. In addition, by controlling the blending ratio of PBT and nylon 12, nylon 12 is dispersed in the "sea phase" PBT in the "island phase" without changing the chemical sharpening performance of the blend to prepare brush filaments, thereby preparing a lodging-resistant PBT /PA12 sharpened toothbrush wire.

Description of drawings

Fig. 1 is the SEM image of the PBT/PA12 compounded granules prepared in Example 5.

Fig. 2 is the optical micrograph of the sharpened toothbrush filament prepared in Example 5.

Detailed ways

The present invention will be further described through specific examples below, and the described examples of the present invention are only used as illustrations of the present invention, and do not limit the scope of the present invention.

Test Methods:

(1) Number average molecular weight test: test by gel permeation chromatography (GPC) system, the equipment model is WATERS1515;

(2) Carboxyl-terminated and amino-terminated content test: test by potentiometric titration (Metrohm 848 automatic potentiometric titrator);

(3) Scanning electron microscope (SEM) test of PBT/PA12 compounded particles: the PBT/PA12 compounded material bar was brittlely broken in liquid nitrogen, and the brittle section was etched with 88% formic acid for 3 minutes, and then gold was sprayed with a scanning electron microscope ( JSG-5900LV, Japan) for section observation.

(4) The lodging resistance performance test of the brush wire: Prepare the toothbrush wire after being sharpened into a standard toothbrush, and test it with a weight of 335g. The test speed is 13mm/s, and the test time is 24h. The lodging resistance effect of the brush wire is determined according to the ratio of the lodging brush wire . Judging criteria are: no lodging: 0-30%; slight lodging: 30-50%; lodging: 50-70%; obvious lodging: 70-90%; complete lodging: 100%

[Preparation Example 1]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of double carboxyl-terminated PBT oligomer: 2330g terephthalic acid (PTA), 1000g1,4-butanediol (BDO) and 2.33g dioctyltin oxide are added to the reactor for nitrogen replacement 3 times, heated Raise the temperature to 240°C and keep it for 1h to carry out the esterification reaction. After the esterification reaction is completed, the temperature is kept at 240° C., and nitrogen gas is purged for 0.5 h to carry out the prepolymerization reaction. After the prepolymerization is completed, add 4.66g of dioctyltin oxide, raise the temperature to 245°C and pump a vacuum to reduce the absolute pressure of the reaction system to below 100Pa, and continue the reaction for 0.5h; The dicarboxyl-terminated PBT oligomer (D-PBT-1) was prepared by water cooling-drying-crushing. The prepared dicarboxy-terminated PBT oligomer (D-PBT-1) had a number average molecular weight of 1001 and a carboxyl-terminated content of 1.999 mmol/g.

b. Preparation of diamino-terminated nylon 12 oligomer: Add 2000g of laurolactam, 590g of dodecanediamine and 240g of ultrapure water into a 10L reactor, replace with nitrogen three times, heat up to 270°C and keep for 5h to complete The ring-opening reaction of laurolactam; after the ring-opening is completed, the pressure is released to normal pressure, the pressure is released and the temperature is lowered to 180°C at the same time, and then vacuumized for 30 minutes to complete the melting polycondensation; after the melting polycondensation is completed, stop vacuuming and protect the . The prepared diamino-terminated nylon 12 oligomer (D-PA12-1) has a number-average molecular weight of 1001 and an amino-terminated content of 1.993 mmol/g;

c. Preparation of amphiphilic block copolymer: drop into 2589g dicarboxy-terminated PBT oligomer (D-PBT-1) and 37g adipic acid in the reaction still equipped with diamino-terminated nylon oligomer, After nitrogen replacement for 3 times, the temperature was raised to 245°C, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45 minutes to make the dicarboxyl-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer undergo amidation reaction to obtain PBT Combined with PA12 block copolymer (B-PBT/PA12-1), after traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 20220.

[Preparation Example 2]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: Prepare dicarboxyl-terminated PBT oligomer (D-PBT-1) according to step a of Preparation Example 1.

b. Preparation of diamino-terminated nylon 12 oligomer: Add 2000g of laurolactam, 257g of dodecanediamine and 240g of ultrapure water into a 10L reactor, replace with nitrogen three times, heat up to 280°C and keep for 5h to complete The ring-opening reaction of laurolactam; after the ring-opening is completed, the pressure is released to normal pressure, and the temperature is lowered to 200 ° C at the same time, and then vacuumized for 45 minutes to complete the melt polycondensation; after the melt polycondensation is completed, stop vacuuming and protect the . The prepared diamino-terminated nylon 12 oligomer (D-PA12-2) has a number-average molecular weight of 2002 and an amino-terminated content of 0.999 mmol/g;

c. Preparation of amphiphilic block copolymer: drop into 1128g of dicarboxy-terminated PBT oligomer (D-PBT-1 ) and 24.5g of adipic acid, the temperature was raised to 245°C after nitrogen replacement for 3 times, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 lower The polymer undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-2), and then undergoes traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 20100.

[Preparation Example 3]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: Prepare dicarboxyl-terminated PBT oligomer (D-PBT-1) according to step a of Preparation Example 1.

b. Preparation of diamino-terminated nylon 12 oligomer: Add 2000g of laurolactam, 165g of dodecanediamine and 240g of ultrapure water into a 10L reactor, replace with nitrogen three times, heat up to 280°C and keep for 5h to complete The ring-opening reaction of laurolactam; after the ring-opening is completed, the pressure is released to normal pressure, and the temperature is lowered to 200°C while the pressure is released, and then vacuumized for 45 minutes to complete the melt polycondensation; after the melt polycondensation is completed, the vacuum is stopped and the inert gas is protected. The prepared diamino-terminated nylon 12 oligomer (D-PA12-3) has a number-average molecular weight of 2992 and an amino-terminated content of 0.669 mmol/g;

c. Preparation of amphiphilic block copolymer: drop into 724g dicarboxy-terminated PBT oligomer and 21g adipic acid in a reactor equipped with diamino-terminated nylon oligomer (D-PA12-3), After nitrogen replacement for 3 times, the temperature was raised to 245°C, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45 minutes to make the dicarboxyl-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer undergo amidation reaction to obtain PBT Combined with PA12 block copolymer (B-PBT/PA12-3), then traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 20050.

[Preparation Example 4]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of double carboxyl-terminated PBT oligomer: 2064g terephthalic acid (PTA), 1000g1,4-butanediol (BDO) and 2.06g dioctyltin oxide are added to the reactor for nitrogen replacement 3 times, heated Raise the temperature to 240°C and keep it for 1h to carry out the esterification reaction. After the esterification reaction was completed, the temperature was kept at 240° C., and the nitrogen gas was purged for 0.75 h to carry out the prepolymerization reaction. After the prepolymerization is completed, add 4.12g of dioctyltin oxide, raise the temperature to 245°C and pump a vacuum to reduce the absolute pressure of the reaction system to below 100Pa, and continue the reaction for 1h; stop the vacuum, add nitrogen to 50kPa, and pass the high temperature melt through Water cooling—drying—crushing to prepare dicarboxyl-terminated PBT oligomer (D-PBT-2). The prepared dicarboxy-terminated PBT oligomer has a number-average molecular weight of 2007 and a carboxyl-terminated content of 0.996mmol/g.

b. Preparation of diamino-terminated nylon 12 oligomer: prepare diamino-terminated PA12 oligomer (D-PA12-1) according to step b of Preparation Example 1.

c. Preparation of amphiphilic block copolymer: drop into 4526g of dicarboxy-terminated PBT oligomer (D-PBT-2 ) and 56g of adipic acid, the temperature was raised to 245°C after nitrogen replacement for 3 times, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer PBT and PA12 block copolymer (B-PBT/PA12-4) were obtained through amidation reaction, and then the amphiphilic block copolymer pellets were obtained through traction-water cooling-cutting-drying. The number average molecular weight of the amphiphilic block copolymer is 20210.

[Preparation Example 5]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: prepare dicarboxyl-terminated PBT oligomer (D-PBT-2) according to step a of Preparation Example 4.

b. Preparation of diamino-terminated nylon 12 oligomer: prepare diamino-terminated PA12 oligomer (D-PA12-2) according to Step b of Preparation Example 2.

c. Preparation of amphiphilic block copolymer: drop into 2170g of dicarboxy-terminated PBT oligomer (D-PBT-2 ) and 32.5g of adipic acid, the temperature was raised to 245°C after nitrogen replacement for 3 times, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 lower The polymer undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-5), and then the amphiphilic block copolymer pellets are obtained through traction-water cooling-cutting-drying. The number average molecular weight of the amphiphilic block copolymer is 20230.

[Preparation Example 6]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of double carboxyl-terminated PBT oligomers: 1987g terephthalic acid (PTA), 1000g1,4-butanediol (BDO) and 1.99g tetrabutyl titanate were added to the reactor for nitrogen replacement 3 times, heated Raise the temperature to 240°C and keep it for 1.5h to carry out the esterification reaction. After the esterification reaction was completed, the temperature was kept at 240° C., and the nitrogen gas was purged for 0.75 h to carry out the prepolymerization reaction. After the prepolymerization is completed, add 3.98g of tetrabutyl titanate, raise the temperature to 245°C and evacuate to reduce the absolute pressure of the reaction system below 100Pa, and continue the reaction for 1.5h; stop the vacuum, add nitrogen to 75kPa, and the high temperature melt The dicarboxyl-terminated PBT oligomer (D-PBT-3) was prepared by water cooling-drying-crushing. The prepared dicarboxyl-terminated PBT oligomer has a number-average molecular weight of 2995 and a carboxyl-terminated content of 0.668mmol/g.

b. Preparation of diamino-terminated nylon 12 oligomer: prepare diamino-terminated PA12 oligomer (D-PA12-2) according to Step b of Preparation Example 2.

c. Preparation of amphiphilic block copolymer: drop into 2167g of dicarboxy-terminated PBT oligomer (D-PBT-3 ) and 27.5g of adipic acid, the temperature was raised to 245°C after nitrogen replacement for 3 times, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 lower The polymer undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-6), and then undergoes traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 29820.

[Preparation Example 7]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: Prepare dicarboxyl-terminated PBT oligomer (D-PBT-3) according to step a of Preparation Example 6.

b. Preparation of diamino-terminated nylon 12 oligomer: Add 2000g of laurolactam, 122g of decanediamine and 240g of ultrapure water into a 10L reaction kettle, replace with nitrogen three times, heat up to 280°C and keep for 5h to complete twelve The ring-opening reaction of lactam; after the ring-opening is completed, the pressure is released to normal pressure, and the temperature is lowered to 200°C while the pressure is released, and then vacuumized for 45 minutes to complete the melt polycondensation; after the melt polycondensation is completed, the vacuum is stopped and the inert gas is protected. The number-average molecular weight of the prepared diamino-terminated nylon 12 oligomer (D-PA12-4) is 2997, and the amino-terminal content is 0.667 mmol/g.

c. Preparation of amphiphilic block copolymer: drop into 2588g of dicarboxy-terminated PBT oligomer (D-PBT-3 ) and 95g of dodecanedioic acid, the temperature was raised to 245°C after nitrogen replacement 3 times, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 30min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 The oligomer undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-7), and then the amphiphilic block copolymer pellets are obtained through traction-water cooling-cutting-drying. The number average molecular weight of the amphiphilic block copolymer is 10400.

[Preparation Comparative Example 8]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: prepare dicarboxyl-terminated PBT oligomer (D-PBT-2) according to step a of Preparation Example 4.

b. Preparation of diamino-terminated nylon 12 oligomer: prepare diamino-terminated PA12 oligomer (D-PA12-2) according to Step b of Preparation Example 2.

c. Preparation of amphiphilic block copolymer: drop into 2170g of dicarboxy-terminated PBT oligomer (D-PBT-2 ) and 100g of adipic acid, nitrogen replacement 3 times and then warming up to 245°C, vacuuming to reduce the absolute pressure of the reaction system to below 1kPa, continue the reaction for 30min to make the dicarboxy-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer The compound undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-1'), and then undergoes traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 5200.

[Preparation Comparative Example 9]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of dicarboxyl-terminated PBT oligomer: prepare dicarboxyl-terminated PBT oligomer (D-PBT-2) according to step a of Preparation Example 4.

b. Preparation of diamino-terminated nylon 12 oligomer: prepare diamino-terminated PA12 oligomer (D-PA12-2) according to Step b of Preparation Example 2.

c. Preparation of amphiphilic block copolymer: drop into 2170g of dicarboxy-terminated PBT oligomer (D-PBT-2 ) and 10g of adipic acid, nitrogen replacement 3 times and then warming up to 245°C, vacuuming to reduce the absolute pressure of the reaction system to below 1kPa, continue the reaction for 60min to make dicarboxy-terminated PBT oligomer and diamino-terminated nylon 12 oligomer The compound undergoes amidation reaction to obtain PBT and PA12 block copolymer (B-PBT/PA12-2'), and then undergoes traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 65500.

[Preparation Comparative Example 10]

Follow the steps below to prepare amphiphilic block copolymers

a. Preparation of double carboxyl-terminated PBT oligomers: 1913g terephthalic acid (PTA), 1000g1,4-butanediol (BDO) and 1.91g dioctyltin oxide were added to the reactor for nitrogen replacement 3 times, heated Raise the temperature to 240°C and keep for 3h to carry out the esterification reaction. After the esterification reaction was completed, the temperature was kept at 240° C., and nitrogen gas was purged for 1 hour to carry out the prepolymerization reaction. After the prepolymerization is completed, add 3.82g of dioctyltin oxide, raise the temperature to 245°C and pump a vacuum to reduce the absolute pressure of the reaction system below 100Pa, and continue the reaction for 2h; stop the vacuum, add nitrogen to 100kPa, and pass the high temperature melt through Water cooling—drying—crushing to prepare dicarboxyl-terminated PBT oligomer (D-PBT-10). The prepared dicarboxyl-terminated PBT oligomer has a number-average molecular weight of 6004 and a carboxyl-terminated content of 0.333 mmol/g.

b. Preparation of diamino-terminated nylon 12 oligomer: Add 2000g of laurolactam, 79g of dodecanediamine and 240g of ultrapure water into a 10L reaction kettle, replace with nitrogen three times, heat up to 290°C and keep for 5h to complete The ring-opening reaction of laurolactam; after the ring-opening is completed, the pressure is released to normal pressure, and the temperature is lowered to 220°C at the same time, and then vacuumized for 60 minutes to complete the melt polycondensation; after the melt polycondensation is completed, stop vacuuming and protect the . The prepared diamino-terminated nylon 12 oligomer (D-PA12-10) has a number-average molecular weight of 6000 and an amino-terminated content of 0.333 mmol/g;

c. the preparation of amphiphilic block copolymer: drop into 2080g dicarboxy-terminated PBT oligomer (D-PBT-10) and 30g adipic acid in the reactor that diaminoterminated nylon oligomer is housed, After nitrogen replacement for 3 times, the temperature was raised to 245°C, the absolute pressure of the reaction system was reduced to below 1kPa by vacuuming, and the reaction was continued for 45 minutes to make the dicarboxyl-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer undergo amidation reaction to obtain PBT Combined with PA12 block copolymer (B-PBT/PA12-3'), followed by traction-water cooling-cutting-drying to obtain amphiphilic block copolymer pellets. The number average molecular weight of the amphiphilic block copolymer is 20320.

Example 1

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: mix 9kg polybutylene terephthalate (Nanxingchen Synthetic Materials Company, PBT1100 AFL, relative viscosity is 0.75), 1kg nylon 12 (Japan Ube, 3020U, relative Viscosity is 1.80), B-PBT/PA12-1 compatibilizer 100g, lubricant EBS 30g, compound antioxidant (equal mass compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer and mix The mixed ingredients were prepared in 20 minutes, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with an aspect ratio of 40-water cooling-cutting-drying to prepare PBT/PA12 mixed granules, and the screw speed was 100rpm. The temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 25—spinneret extrusion—water cooling setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 160°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 30%; the treatment temperature is 120° C.; the treatment time is 40 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 2

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , relative viscosity is 1.80), B-PBT/PA12-2 compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 10g add to high-speed mixer The mixture was mixed for 20 minutes to prepare the mixed ingredients, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with a length-to-diameter ratio of 45—water cooling—cutting—drying to prepare PBT/PA12 mixed pellets, and the screw speed was 100rpm, the temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 30—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the die head is set at 200-280°C; the hot drawing is carried out in a hot oven at 150°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 30%; the treatment temperature is 120° C.; the treatment time is 80 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 3

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 6kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 4kg nylon 12 (Japan Ube, 3020U, relative Viscosity is 1.80), B-PBT/PA12-3 compatibilizer 500g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer and mix After 20 minutes, the mixed ingredients were prepared, and then the mixed ingredients were melt blended and extruded by a twin-screw extruder with an aspect ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed granules, and the screw speed was 100rpm. The temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 28—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 140°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 50%; the treatment temperature is 140° C.; the treatment time is 80 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 4

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (South Star Synthetic Materials Company, PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Evonik, Germany, L1940, relative viscosity is 1.89), B-PBT/PA12-4 compatibilizer 300g, lubricant EBS10g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 50g add high-speed mixer The mixture was mixed for 20 minutes to prepare the mixed ingredients, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with a length-to-diameter ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, and the screw speed was 100rpm, the temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 28—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 150°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 40%; the treatment temperature is 120° C.; the treatment time is 60 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 5

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , relative viscosity is 1.80), B-PBT/PA12-5 compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal mass compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer The mixture was mixed for 20 minutes to prepare the mixed ingredients, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with a length-to-diameter ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, and the screw speed was 100rpm, the temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 28—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 150°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 30%; the treatment temperature is 140° C.; the treatment time is 60 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 6

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , relative viscosity is 1.80), B-PBT/PA12-6 compatibilizer 300g, lubricant EBS 50g, compound antioxidant (equal mass compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer The mixture was mixed for 20 minutes to prepare the mixed ingredients, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with a length-to-diameter ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, and the screw speed was 100rpm, the temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 28—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 150rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 150°C, and the draw ratio is 5; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 40%; the treatment temperature is 100°C; the treatment time is 80 minutes; after the silk cake is sharpened, the silk cake is washed with water until it is neutral (PH=7), and then used Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Example 7

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , relative viscosity is 1.80), B-PBT/PA12-7 compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal mass compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer The mixture was mixed for 20 minutes to prepare the mixed ingredients, and then the mixed ingredients were melt blended and extruded using a twin-screw extruder with a length-to-diameter ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, and the screw speed was 100rpm, the temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation steps: Plasticize the mixed pellets prepared in step (1) through a single-screw extruder with an aspect ratio of 28—spinneret extrusion—water cooling and setting—heat stretching—winding Rolls—hardened by heat treatment—encapsulated and cut to prepare silk cakes. The speed of the single-screw extruder is 100rpm, and the temperature from the feeding section to the head is set at 200-280°C; the hot drawing is carried out in a hot oven at 150°C, and the draw ratio is 4; the diameter of the monofilament after hot drawing The tow is 7mil; the tow is hardened by heat treatment in a nitrogen-filled oven, the temperature of the nitrogen-filled oven is 120°C, and the treatment time is 2h; the diameter of the cut silk cake bundle is 50±2mm, and the height is 30±2mm.

(3) Silk cake sharpening treatment step: the silk cake prepared in step (2) is placed in a silk cake sharpening tank filled with a sharpening liquid for sharpening treatment—cleaning—drying to prepare sharpened toothbrush filaments. The sharpening solution used is NaOH aqueous solution with a concentration of 40%; the treatment temperature is 120° C.; the treatment time is 60 minutes; Dry it in a vacuum oven at 80° C. for 12 hours to obtain the finished sharpened toothbrush filament.

Comparative example 1

Prepare PBT grinding wire according to the following method:

(1) PBT/antioxidant/lubricant mixed granular material preparation steps: 10kg polybutylene terephthalate (South Star Synthetic Material Company, PBT1100 AFL, relative viscosity is 0.75), lubricant EBS 30g, Add 30 g of compound antioxidant (an equal mass compound of Antioxidant 1098 and Antioxidant 168) into a high-speed mixer and mix for 20 minutes to make a mixed batch, and then use a twin-screw extruder with an aspect ratio of 42 for the mixed batch Perform melt blending extrusion-water cooling-pelletizing-drying to prepare PBT/antioxidant/lubricant mixed pellets, the screw speed is 100rpm, and the temperature from the feeding section to the machine head is set at 180-250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/antioxidant/lubricant mixed granular material was prepared into a PBT silk cake.

(3) Silk cake sharpening treatment step: prepare the above-mentioned PBT/antioxidant/lubricant silk cake into PBT sharpened toothbrush filament according to step (3) of Example 5.

Comparative example 2

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , the relative viscosity is 1.80), 30g of lubricant EBS, compound antioxidant (equal mass compound of antioxidant 1098 and antioxidant 168) 30g were added in a high-speed mixer and mixed for 20min to prepare a mixed batch, and then the mixed batch A twin-screw extruder with an aspect ratio of 42 was used for melt blending extrusion-water cooling-pelletizing-drying to prepare PBT/PA12 compound pellets, the screw speed was 100rpm, and the temperature from the feeding section to the head was set at 180 -250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/PA12 mixed granular material was prepared into a PBT/PA12 silk cake.

(3) Silk cake sharpening treatment step: prepare the above PBT/PA12 silk cake into PBT/PA12 sharpened toothbrush filament according to step (3) of Example 5.

Comparative example 3

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , the relative viscosity is 1.80), B-PBT/PA12-1' compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 30g add high speed Mix in the mixer for 20 minutes to prepare the mixed ingredients, and then use the twin-screw extruder with an aspect ratio of 42 to carry out melt blending and extrusion-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, the screw speed It is 100rpm, and the temperature from the feeding section to the machine head is set at 180-250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/PA12 mixed granular material was prepared into a PBT/PA12 silk cake.

(3) Silk cake sharpening treatment step: prepare the above PBT/PA12 silk cake into PBT/PA12 sharpened toothbrush filament according to step (3) of Example 5.

Comparative example 4

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , the relative viscosity is 1.80), B-PBT/PA12-2' compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 30g add high speed Mix in the mixer for 20 minutes to prepare the mixed ingredients, and then use the twin-screw extruder with an aspect ratio of 42 to carry out melt blending and extrusion-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, the screw speed It is 100rpm, and the temperature from the feeding section to the machine head is set at 180-250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/PA12 mixed granular material was prepared into a PBT/PA12 silk cake.

(3) Silk cake sharpening treatment step: prepare the above PBT/PA12 silk cake into PBT/PA12 sharpened toothbrush filament according to step (3) of Example 5.

Comparative example 5

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 4kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 6kg nylon 12 (Japan Ube, 3020U, relative Viscosity is 1.80), B-PBT/PA12-5 compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 30g add to high-speed mixer and mix After 20 minutes, the mixed ingredients were prepared, and then the mixed ingredients were melt blended and extruded by a twin-screw extruder with an aspect ratio of 42-water cooling-cutting-drying to prepare PBT/PA12 mixed granules, and the screw speed was 100rpm. The temperature from the feeding section to the machine head is set to 180-250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/PA12 mixed granular material was prepared into a PBT/PA12 silk cake.

(3) Silk cake sharpening treatment steps: According to the step (3) of Example 5, the above-mentioned PBT/PA12 silk cake is sharpened. After reaching the set time, it is found that the end of the brush wire has not been sharpened, indicating that the formula is prepared The brush filaments cannot be sharpened with NaOH solution.

Comparative example 6

Prepare PBT/PA12 sharpened wire as follows:

(1) Preparation steps of PBT/PA12 mixed granules: 7.5kg polybutylene terephthalate (Nanxingchen Synthetic Materials Co., Ltd., PBT1100 AFL, relative viscosity is 0.75), 2.5kg nylon 12 (Japan Ube, 3020U , the relative viscosity is 1.80), B-PBT/PA12-3' compatibilizer 300g, lubricant EBS 30g, compound antioxidant (equal quality compound of antioxidant 1098 and antioxidant 168) 30g add high speed Mix in the mixer for 20 minutes to prepare the mixed ingredients, and then use the twin-screw extruder with an aspect ratio of 42 to carry out melt blending and extrusion-water cooling-cutting-drying to prepare PBT/PA12 mixed pellets, the screw speed It is 100rpm, and the temperature from the feeding section to the machine head is set at 180-250°C.

(2) Silk cake preparation step: according to the step (2) of Example 5, the above-mentioned PBT/PA12 mixed granular material was prepared into a PBT/PA12 silk cake.

(3) Silk cake sharpening treatment step: prepare the above PBT/PA12 silk cake into PBT/PA12 sharpened toothbrush filament according to step (3) of Example 5.

In order to characterize the lodging resistance of the brush filaments prepared in each example, the toothbrush filaments prepared in each example were prepared into standard toothbrushes, and tested with a weight of 335g, the test speed was 13mm/s, and the test time was 24h. Lodging effect. Judging criteria are: no lodging: 0-30%; slight lodging: 30-50%; lodging: 50-70%; obvious lodging: 70-90%; complete lodging: 100%. The chemical sharpening performance and lodging resistance test results of the brush filaments prepared by each example are as follows:

Table 1. Test results of chemical sharpening performance and lodging resistance performance of brush filaments

From the chemical sharpening and lodging resistance results of the examples and comparative examples in Table 1, it can be seen that the amphiphilic block copolymer prepared by the present invention can effectively improve the compatibility of nylon 12 and PBT to realize that PA12 has the same effect on PBT. The submicron size is dispersed in the matrix, and the submicron size dispersed PA12 phase can improve the lodging resistance of PBT brush filaments and maintain its chemical sharpening ability.

When no amphiphilic block copolymer was added (comparative example 2), PA12 was dispersed in the PBT matrix with a large size, and the presence of a large-size phase interface deteriorated the lodging resistance of the brush filament.

When the molecular weight of the amphiphilic block copolymer is too small (comparative example 3) or too large (comparative example 4), due to the high mismatch between the amphiphilic block copolymer and the melt viscosity of PBT and PA12, the expected increase cannot be achieved. The capacity effect, PA12 dispersed phase size is larger, the corresponding brush filament lodging resistance performance is relatively poor.

When the amount of PA12 added is too high (comparative example 5), the phase inversion of the PBT/PA12 blend system occurs, PA12 is the continuous phase (sea phase), and PBT is the dispersed phase (island phase), and the prepared brush filaments cannot achieve NaOH solution chemistry. Sharpen.

When the molecular weight of dicarboxyl-terminated PBT and diamino-terminated PA12 is too high for the preparation of amphiphilic block copolymers, the PBT/PA12 block copolymer will undergo phase separation and deteriorate the compatibilization effect, and the size of the PA12 dispersed phase will be larger , The brush wire has poor lodging resistance.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the method of the present invention, some improvements and supplements can also be made, and these improvements and supplements should also be considered Be the protection scope of the present invention.

Claims (10)

1. The lodging-resistant PBT/PA12 sharpened toothbrush wire comprises the following raw materials in parts by weight:

2. the lodging resistant PBT/PA12 tipped toothbrush of claim 1, characterized in that the PBT relative viscosity is 0.6-0.85 (phenol-1, 2-tetrachloroethane = 1:1 (w/w) as solvent, 0.005g/ml concentration), more preferably 0.75; the nylon 12 has a relative viscosity of 1.60 to 1.90 (m-cresol as solvent, 0.005g/ml concentration), more preferably 1.80.

3. The lodging-resistant PBT/PA12 tipped toothbrush filament according to claim 1 or 2, characterized in that the amphiphilic block copolymer is a block copolymer of a dicarboxyl-terminated PBT oligomer and a bisamino-terminated nylon 12 oligomer produced by amidation reaction.

4. A lodging resistant PBT/PA12 tipped toothbrush filament according to any of claims 1-3, characterized in that the method of preparing the amphiphilic block copolymer comprises the steps of:

(1) Preparation of dicarboxyl-terminated PBT oligomer:

(1-1) under the inert gas atmosphere, terephthalic acid, 1, 4-butanediol and a catalyst 1 are kept at 220-240 ℃ for 1-3 hours to carry out esterification reaction; keeping 220-240 ℃ and purging nitrogen for 0.5-1h to perform prepolymerization reaction;

after the prepolymerization is completed, adding a catalyst 2, and reacting for 0.5-2 hours at 240-250 ℃ under the absolute pressure of 100 Pa; stopping vacuumizing, adding inert gas to 50-100kPa, cooling the high-temperature melt by water cooling, drying and crushing to prepare the dicarboxyl end-capped PBT oligomer;

2) Preparation of a diamino terminated nylon 12 oligomer:

(2-1) under an inert gas atmosphere, the laurolactam, the diamine end-capping agent and water are kept at 270-290 ℃ for 3-7 hours, preferably 5 hours, to complete the ring-opening reaction of the laurolactam;

(2-2) after ring opening is completed, pressure is released to normal pressure, the temperature is reduced to 180-220 ℃ at the same time, and then vacuum pumping treatment is carried out for 30-60min, so that melt polycondensation is completed; stopping vacuumizing after the melt polycondensation is completed, and protecting by inert gas;

(3) Preparation of amphiphilic block copolymer:

under inert gas atmosphere, the diamino-terminated nylon 12 oligomer, the dicarboxyl-terminated PBT oligomer and the molecular weight regulator react for 30-60min at 240-250 ℃ under absolute pressure of below 1kPa, so that the dicarboxyl-terminated PBT oligomer and the diamino-terminated nylon 12 oligomer are subjected to amidation reaction to obtain a PBT and PA12 segmented copolymer, and the segmented copolymer is subjected to traction, water cooling, granulating and drying.

5. The lodging resistant PBT/PA12 tipped toothbrush filament of any of claims 1-4 wherein the dicarboxyl terminated PBT oligomer prepared has a number average molecular weight of 1000 to 3000; the carboxyl end group content of the dicarboxyl end-capped PBT oligomer is 0.65-2.0mmol/g.

6. The lodging resistant PBT/PA12 tipped toothbrush of any of claims 1-5 wherein the nylon 12 oligomer produced has a number average molecular weight of 1000-3000; the amino end content of the nylon 12 oligomer is 0.65-2.0mmol/g.

7. The lodging resistant PBT/PA12 tipped toothbrush of claim 4 wherein in step (3) the ratio of moles of terminal carboxyl groups of the dicarboxyl terminated PBT oligomer to moles of terminal amino groups of the dicarboxyl terminated nylon 12 oligomer is 1:1.

8. The lodging resistant PBT/PA12 tipped toothbrush filament according to any of claims 1 to 7, characterized in that the amphiphilic block copolymer has a number average molecular weight of 10000-30000, preferably 20000.

9. The lodging-resistant PBT/PA12 sharpened toothbrush filament according to any one of claims 1 to 8, wherein the antioxidant is selected from one or more of antioxidant 1010, antioxidant 1098, antioxidant 168 and antioxidant H10, preferably an antioxidant 1010 and antioxidant 168 1:1 equal mass compound system; the lubricant is selected from one or more of ethylene bisstearamide, oleamide, silicone oil and paraffin, preferably ethylene bisstearamide.

10. A process for preparing the lodging resistant PBT/PA12 tipped toothbrush filaments of any one of claims 1 to 9 comprising the steps of:

(a) The preparation method of the PBT/PA12 mixed granular material comprises the following steps: adding polybutylene terephthalate, nylon 12, amphiphilic block copolymer, lubricant and antioxidant into a high-speed stirrer, mixing for 10-20min to obtain a mixed material, and then carrying out melt blending extrusion on the mixed material by using a double-screw extruder, water-cooling, granulating, drying, and preparing PBT/PA12 mixed granule;

(b) The preparation method of the spinning cake comprises the following steps: preparing a spinning cake by adopting a melt spinning production line, plasticizing the mixed granular material prepared in the step (a) by a single screw extruder, extruding by a spinneret plate, performing water-cooling shaping, hot stretching, winding a take-up roller, performing heat treatment hardening, packaging and cutting to prepare the spinning cake;

(c) Sharpening the spinning cake: and (c) placing the spinning cake prepared in the step (b) into a spinning cake sharpening groove filled with sharpening liquid for sharpening, cleaning and drying to prepare the sharpening toothbrush filament.

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