CN118006133A - Nylon encapsulated TPE composite material and preparation method and application thereof - Google Patents

Abstract

The invention discloses a nylon encapsulated TPE composite material and a preparation method and application thereof. The nylon encapsulated TPE composite of the present invention comprises: hydrogenated styrenic elastomers, mineral oils, polypropylene, polycaprolactam, thermoplastic polyamide elastomers, maleic anhydride grafted polypropylene, maleic anhydride grafted olefin copolymer elastomers, maleic anhydride grafted hydrogenated styrenic elastomers, fillers and adjuvants. The nylon encapsulated TPE composite material combines polycaprolactam and thermoplastic polyamide elastomer, and is matched with other components, and the polycaprolactam is utilized to improve the strength of the composite material and the encapsulation performance; the appearance of the composite material is improved by increasing the content of the elastomer through the thermoplastic polyamide elastomer, and the compatibility of polycaprolactam and the whole composite material is improved, so that the nylon-encapsulated TPE composite material with high adhesive force, excellent mechanical property and good appearance is obtained.

Description

A nylon-coated TPE composite material and its preparation method and application

Technical Field

The present invention relates to the technical field of polymer compound compositions, and more specifically, to a nylon encapsulated TPE composite material and a preparation method and application thereof.

Background technique

Thermoplastic elastomer (TPE) is a polymer composite material that has both the processing properties of thermoplastics and the physical properties of vulcanized rubber. It is widely used in electronic appliances, communications, daily necessities, and automobiles. Among them, an important application of TPE is as a coating material (encapsulation), which is to encapsulate TPE soft rubber material on the surface of other materials, using its good anti-slip properties and good elastic touch to improve the touch feel of the product and enhance the grip. At present, the coated materials mainly include general plastics (PP, GPPS, HIPS, ABS) and engineering plastics (PC, PC/ABS, PA, POM), among which nylon (PA) is a highly polar polymer material, while conventional TPE is mainly composed of SEBS, white oil, PP, POE and other components, which is a non-polar material, resulting in poor adhesion between it and nylon.

To solve the above problems, the prior art discloses a novel TPE nylon encapsulation material and a preparation method thereof. The TPE nylon encapsulation material comprises: styrene elastomer, white oil, maleic anhydride grafted polystyrene elastomer, maleic anhydride grafted polyethylene, polypropylene, calcium carbonate and a stabilizer. Maleic anhydride grafted polystyrene elastomer is used to improve the bonding strength between TPE encapsulation and nylon, so as to improve the bonding performance between TPE and nylon. However, styrene polymers (PS, HIPS, AS, ABS) easily cause cohesive failure of the material, thereby reducing the tensile properties of the TPE nylon encapsulation material.

For another example, the prior art also discloses a TPE nylon encapsulated granular material with high fluidity and high adhesion, including styrene elastomer, white oil, maleic anhydride grafted polystyrene elastomer, maleic anhydride grafted polyethylene, maleic anhydride grafted POE, polypropylene and calcium carbonate. By introducing maleic anhydride grafted POE, the adhesion and compatibility between polar materials and non-polar materials are improved to increase the bonding strength between TPE and nylon; however, maleic anhydride grafted POE or maleic anhydride grafted polyethylene has low compatibility with polypropylene and maleic acid styrene elastomer, resulting in poor mechanical properties and appearance properties of the PE nylon encapsulated material.

Summary of the invention

The purpose of the present invention is to overcome the defects and shortcomings of existing TPE nylon encapsulated materials that are difficult to have high adhesion, excellent mechanical properties and good appearance, and to provide a nylon encapsulated TPE composite material.

Another object of the present invention is to provide a method for preparing a nylon-encapsulated TPE composite material.

Another object of the present invention is to provide an application of the above-mentioned dragon rubber-coated TPE composite material in the rubber coating of power tool handles, game handles and automotive parts.

Another object of the present invention is to provide a rubber-coated nylon product.

The above-mentioned purpose of the present invention is achieved through the following technical solutions:

The present invention protects a nylon encapsulated TPE composite material, which comprises the following components by weight:

10-30 parts of hydrogenated styrene elastomer, 20-60 parts of mineral oil, 5-20 parts of polypropylene, 5-15 parts of polycaprolactam, 5-15 parts of thermoplastic polyamide elastomer, 1-20 parts of maleic anhydride grafted polypropylene, 1-20 parts of maleic anhydride grafted olefin copolymer elastomer, 1-20 parts of maleic anhydride grafted hydrogenated styrene elastomer, 0-50 parts of filler, and 0-2 parts of additives.

The nylon encapsulated TPE composite material of the present invention combines polypropylene, maleic anhydride grafted polypropylene and polycaprolactam, and is used in combination with thermoplastic polyamide elastomer, hydrogenated styrene elastomer and maleic anhydride grafted hydrogenated styrene elastomer, which can not only effectively improve the strength and toughness of the composite material, but also significantly improve its encapsulation performance.

The addition of thermoplastic polyamide elastomer can, on the one hand, increase the elastomer content to improve the feel and appearance of the composite material. On the other hand, the amide group in the polyamide elastomer can be compatible with polycaprolactam, while the polyester or polyether group can promote compatibility with hydrogenated styrene elastomers, thereby improving the compatibility of polycaprolactam with the composite material as a whole, thereby compensating for the defects of poor compatibility, poor appearance and poor plasticization caused by the addition of polycaprolactam. The addition of maleic anhydride grafted hydrogenated styrene elastomer component, on the one hand, increases the content of grafted material to compensate for the insufficient adhesion caused by the addition of polypropylene; on the other hand, it is equivalent to increasing the content of hydrogenated styrene elastomer in the composite material, which further improves the tensile strength of the composite material.

It should also be noted that the total mass fraction of polycaprolactam and thermoplastic polyamide elastomer in the nylon encapsulated TPE composite material is 4% to 38%; wherein the mass ratio of polycaprolactam to thermoplastic polyamide elastomer is (0.6 to 1.5):1, preferably (0.8 to 1.2):1, specifically 0.7:1, 0.9:1, 1:1, 1.1:1, 1.3:1 or 1.4:1. In addition, compared with styrene elastomers or maleic anhydride grafted styrene elastomers, hydrogenated styrene elastomers or maleic anhydride grafted hydrogenated styrene elastomers have better strength and weather resistance, and are more suitable for the application requirements of encapsulated materials.

Specifically, the mineral oil is at least one of silicone oil, paraffin oil, cycloalkane oil or aromatic oil; the polypropylene is at least one of homopolymer polypropylene, block copolymer polypropylene or random copolymer polypropylene, wherein the block copolymer polypropylene is obtained by polymerization of ethylene and propylene, and the random copolymer polypropylene is obtained by polymerization of ethylene and propylene; the maleic anhydride grafted polypropylene is at least one of maleic anhydride grafted homopolymer polypropylene, maleic anhydride grafted copolymer polypropylene or maleic anhydride grafted random copolymer polypropylene.

Preferably, the nylon encapsulated TPE composite material comprises the following components in parts by weight:

15-25 parts of hydrogenated styrene elastomer, 30-50 parts of mineral oil, 10-15 parts of polypropylene, 8-12 parts of polycaprolactam, 8-12 parts of thermoplastic polyamide elastomer, 10-15 parts of maleic anhydride grafted polypropylene, 10-15 parts of maleic anhydride grafted olefin copolymer elastomer, 10-15 parts of maleic anhydride grafted hydrogenated styrene elastomer, 10-15 parts of filler, and 0.1-1.5 parts of additives.

Optionally, the melting point of the polycaprolactam is less than 240° C., preferably 200-220° C. TPE elastomer cannot withstand high temperature extrusion, therefore, considering the current TPE molding process, the melting point of the polycaprolactam is selected to be less than 240° C., preferably 200-220° C., otherwise it will be impossible to process and extrude.

Optionally, the hydrogenated styrene elastomer is at least one of a hydrogenated styrene-butadiene block copolymer or a hydrogenated styrene-isoprene block copolymer; the maleic anhydride grafted hydrogenated styrene elastomer is at least one of a maleic anhydride grafted hydrogenated styrene-butadiene block copolymer or a maleic anhydride grafted hydrogenated styrene-isoprene block copolymer.

Specifically, the thermoplastic polyamide elastomer is at least one of a polyether block amide block copolymer, a polyether ester amide block copolymer or a polyester amide block copolymer.

Optionally, the maleic anhydride grafted olefin copolymer elastomer is at least one of a maleic anhydride grafted ethylene-propylene copolymer elastomer or a maleic anhydride grafted ethylene-octene copolymer elastomer.

Specifically, the filler is at least one of white carbon black, wollastonite, calcium carbonate, glass beads, talc, kaolin, diatomaceous earth, barium sulfate or mica; the auxiliary agent is at least one of an antioxidant, a light stabilizer or a lubricant.

Optionally, the antioxidant may be one or more of 2,6-di-tert-butyl-4-methylphenol, antioxidant 1010, antioxidant 1076, antioxidant 1790, antioxidant 168 or antioxidant 626;

The above-mentioned light stabilizer can be a compound mixture of a hindered amine light stabilizer and a triazine light stabilizer, for example, the mass ratio of the hindered amine light stabilizer to the triazine light stabilizer is 2:(0.5-1.5); the hindered amine light stabilizer can be one or more of light stabilizer 622, light stabilizer 770, light stabilizer 944, light stabilizer 783, light stabilizer 791, light stabilizer 3853, light stabilizer 292 or light stabilizer 123; the triazine light stabilizer is one or more of UV-234, UV-236 or UV-2373.

The lubricant is one or more of vinyl bisstearamide, hydroxy fatty acid lubricant, erucic acid amide, zinc stearate, magnesium stearate or polyethylene wax.

The present invention also protects a method for preparing a nylon encapsulated TPE composite material, comprising the following steps:

S1. The hydrogenated styrene elastomer is mixed with mineral oil to form a solid one-step material;

S2. The solid first-step material in S1 is mixed with polypropylene, polycaprolactam, thermoplastic polyamide elastomer, maleic anhydride grafted polypropylene, maleic anhydride grafted olefin copolymer elastomer, maleic anhydride grafted hydrogenated styrene elastomer, filler and additives, and melt-extruded to obtain a nylon encapsulated TPE composite material.

Optionally, step S1 specifically comprises: adding hydrogenated styrene elastomer into a high-speed stirring device, and then adding mineral oil in a required proportion and spraying and mixing evenly to form a solid one-step material;

In step S2, a twin-screw extruder may be used for melt extrusion, the aspect ratio of the twin-screw extruder is ≥42:1, and the temperature of melt extrusion is 170-250°C.

The application of the above-mentioned nylon coated TPE composite material in the coating of power tool handles, game controllers and automotive parts is also within the protection scope of the present invention.

The present invention also protects a rubber-coated nylon product, comprising a nylon matrix and a coating agent coated on the surface of the nylon matrix, wherein the coating agent is the above-mentioned nylon rubber-coated TPE composite material.

Compared with the prior art, the present invention has the following beneficial effects:

The nylon encapsulated TPE composite material of the present invention combines polypropylene, maleic anhydride grafted polypropylene and polycaprolactam, and is used in combination with thermoplastic polyamide elastomer, hydrogenated styrene elastomer and maleic anhydride grafted hydrogenated styrene elastomer. The polycaprolactam contains a large number of amide groups, which, after co-acting with polypropylene and maleic anhydride grafted polypropylene, can not only effectively improve the strength and toughness of the composite material, but also significantly improve its encapsulation performance; and the addition of the thermoplastic polyamide elastomer can increase the elastomer content to improve the feel and appearance of the composite material, and can also improve the compatibility of polycaprolactam with the composite material as a whole, thereby compensating for the defects of poor compatibility, poor appearance and poor plasticization caused by the addition of polycaprolactam, and obtaining a nylon encapsulated TPE composite material with high adhesion, excellent mechanical properties and good appearance.

Detailed ways

The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

1. Raw materials and reagents

(1) Hydrogenated styrene elastomer

A: Hydrogenated styrene-butadiene block copolymer, brand SEBS 7551, manufacturer: Lee Chang-jung, Taiwan, China;

(2) Mineral oil

B: cycloparaffin oil, grade 500N, commercially available;

(3) Polypropylene

C1: random copolymer polypropylene, brand PP RJ766MO, manufacturer Borouge Chemical;

C2: block copolymer polypropylene, brand PP K7100, manufacturer China Yanshan Petrochemical;

C3: Homopolymer polypropylene, brand PP HP-500N, manufacturer Basel.

(4) Polyamide

D1: polycaprolactam-1 (PA6), melting point 214, brand MAZMID-B-153, manufacturer Mazzaferro, Brazil;

D2: polycaprolactam-2 (PA6), melting point 203°C, grade 126, manufacturer Austria SAX;

D3: Polylaurolactam (PA612), melting point 218°C, brand Zytel 151L, manufacturer DuPont, USA.

(5) Thermoplastic polyamide elastomer

E1: block polyetheramide elastomer, brand name Pebax 5533SA 01, manufacturer Arkema, France;

E2: Polyether TPU, brand 750U, manufacturer Covestro;

(6) Maleic anhydride grafted polypropylene

F: Maleic anhydride graft copolymer polypropylene, grade AD-105, manufacturer: Nanhai Bochen Polymer, China;

(7) Maleic anhydride grafted olefin copolymer elastomer

G: Maleic anhydride grafted ethylene-octene copolymer elastomer, brand W1A, manufacturer China Coase;

(8) Maleic anhydride grafted hydrogenated styrene elastomer

H: maleic anhydride grafted hydrogenated styrene-butadiene block copolymer, brand SEBS KRATON FG1901, manufacturer Kraton, USA;

(9) The filler is heavy calcium carbonate, brand CC903, manufacturer China Kelong Powder;

(10) The auxiliary agent is prepared by compounding an antioxidant and a light stabilizer in a mass ratio of 6:5. Any antioxidant and light stabilizer can be applicable to the present invention. The types of the antioxidant and the light stabilizer are not limited. The antioxidant can be a single antioxidant or a combination of multiple antioxidants. To better illustrate the effect of the present invention, the antioxidants in the examples and comparative examples are prepared by compounding Irganox 1010 and Irganox 1076 in a mass ratio of 1:5. The light stabilizer is specifically Cyasorb UV-3808pps.

2. The nylon encapsulated TPE composite materials of the embodiments and comparative examples of the present invention are prepared by the following preparation method:

S1. The hydrogenated styrene elastomer is mixed with mineral oil to form a solid one-step material;

S2. The solid first-step material in S1 is mixed with polypropylene, polycaprolactam, thermoplastic polyamide elastomer, maleic anhydride grafted polypropylene, maleic anhydride grafted olefin copolymer elastomer, maleic anhydride grafted hydrogenated styrene elastomer, filler and additives, and then added into a twin-screw extruder for melt extrusion to obtain a nylon encapsulated TPE composite material; wherein the aspect ratio of the twin-screw extruder is 42:1, and the temperature of melt extrusion is 200-240°C.

3. Performance testing

(1) Adhesion strength test method: According to GB/T 7760-2003 standard test, the nylon encapsulated TPE composite material in each embodiment and comparative example is injection molded onto a nylon substrate sample of PA6+30% (mass fraction relative to PA6) glass fiber using an injection molding machine on a specific mold, and the injection molding temperature is 235°C. After being placed at room temperature for 24 hours, it is stretched by a high-end stretching machine for a 90° peel test to measure the adhesion between the nylon encapsulated TPE composite material and the nylon substrate sample; wherein, the adhesion strength grades are divided as follows:

A: Can be peeled off easily, the peeling surface is smooth and has no residue;

B: The peeling force is large, and the residue on the peeling surface is as high as 50%;

C: Difficult to peel off corners, 50%-99% residue, high peeling force;

D: It is difficult to peel off the edges and corners, TPE is broken, and the peeling force is very large.

(2) Tensile strength test method: According to ISO527-2012 standard test, the nylon encapsulated TPE composite material in each embodiment and comparative example was injection molded into a 2*100*100 mm standard square plate, and then cut into 2-type specimens using a cutter. After being placed at room temperature for 24 hours, the tensile machine was used for testing. The molding cycle was based on the cycle of the injection molding tensile specimen.

(3) Appearance test method: After the nylon encapsulated TPE composite material in each embodiment and comparative example is injection molded into a 2*100*100 mm standard square plate, it is placed at room temperature for 24 hours and then the morphology is observed by naked eyes to see whether there is moire. The appearance grade is divided into the following:

A: The surface is not shiny and has severe moire;

B: The surface is not shiny and has slight moire;

C: No moire, but other patterns appear;

D: The surface is bright and has no lines.

Examples 1 to 10 and Comparative Examples 1 to 4

The weight proportions of the components in the nylon encapsulated TPE composite materials in Examples 1 to 10 and Comparative Examples 1 to 4 are shown in Table 1.

Table 1 Weight percentage of each component of the nylon encapsulated TPE composite material in Examples 1 to 10 and Examples 1 to 4

The performance test results of the nylon encapsulated TPE composite materials in each embodiment and comparative example according to the above-mentioned method are shown in Table 2.

Table 2 Test results of various embodiments and comparative examples

According to the data in Table 1, the nylon encapsulated TPE composite materials in Examples 1 to 10 not only have excellent bonding strength, with a bonding grade of B or above and a bonding force of 2.3 N/mm or above; they also have good appearance performance, with an appearance grade of C or above; they also have good tensile properties, with a tensile strength of 2.4 MPa or above, indicating that the nylon encapsulated TPE composite material of the present invention has high bonding strength, excellent mechanical properties and good appearance.

At the same time, it can be seen from Examples 1 to 3 that the type of polypropylene has little effect on the appearance of the nylon encapsulated TPE composite material, and mainly affects the adhesion and bonding grade of the nylon encapsulated TPE composite material. Compared with homopolymer polypropylene, random copolymer polypropylene and copolymer polypropylene have better bonding properties, and random copolymer polypropylene is better than copolymer polypropylene. In addition, according to Example 1, Comparative Examples 2 and 3, it can be seen that only when polycaprolactam and thermoplastic polyamide elastomer work together can the bonding performance and appearance performance of the nylon encapsulated TPE composite material be significantly improved.

The above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. A nylon encapsulated TPE composite material, characterized in that it comprises the following components by weight: 10-30 parts of hydrogenated styrene elastomer, 20-60 parts of mineral oil, 5-20 parts of polypropylene, 5-15 parts of polycaprolactam, 5-15 parts of thermoplastic polyamide elastomer, 5-20 parts of maleic anhydride grafted polypropylene, 5-20 parts of maleic anhydride grafted olefin copolymer elastomer, 5-20 parts of maleic anhydride grafted hydrogenated styrene elastomer, 0-50 parts of filler, and 0-2 parts of additives. 2. The nylon encapsulated TPE composite material according to claim 1, characterized in that it comprises the following components in parts by weight: 15-25 parts of hydrogenated styrene elastomer, 30-50 parts of mineral oil, 10-15 parts of polypropylene, 8-12 parts of polycaprolactam, 8-12 parts of thermoplastic polyamide elastomer, 10-15 parts of maleic anhydride grafted polypropylene, 10-15 parts of maleic anhydride grafted olefin copolymer elastomer, 10-15 parts of maleic anhydride grafted hydrogenated styrene elastomer, 10-15 parts of filler, and 0.1-1.5 parts of additives. 3. The nylon encapsulated TPE composite material according to claim 1, characterized in that the melting point of the polycaprolactam is less than 240°C. 4. The nylon encapsulated TPE composite material according to claim 3, characterized in that the melting point of the polycaprolactam is 200-220°C. 5. The nylon encapsulated TPE composite material according to claim 1, characterized in that the hydrogenated styrene elastomer is at least one of a hydrogenated styrene-butadiene block copolymer or a hydrogenated styrene-isoprene block copolymer; The maleic anhydride grafted hydrogenated styrene elastomer is at least one of a maleic anhydride grafted hydrogenated styrene-butadiene block copolymer or a maleic anhydride grafted hydrogenated styrene-isoprene block copolymer. 6. The nylon encapsulated TPE composite material according to claim 1, characterized in that the thermoplastic polyamide elastomer is at least one of a polyetheramide block copolymer, a polyetheresteramide block copolymer or a polyesteramide block copolymer. 7. The nylon encapsulated TPE composite material according to claim 1, characterized in that the maleic anhydride grafted olefin copolymer elastomer is at least one of a maleic anhydride grafted ethylene-propylene copolymer elastomer or a maleic anhydride grafted ethylene-octene copolymer elastomer. 8. A method for preparing the nylon encapsulated TPE composite material according to any one of claims 1 to 7, characterized in that it comprises the following steps: S1. The hydrogenated styrene elastomer is mixed with mineral oil to form a solid one-step material; S2. The solid first-step material in S1 is mixed with polypropylene, polycaprolactam, thermoplastic polyamide elastomer, maleic anhydride grafted polypropylene, maleic anhydride grafted olefin copolymer elastomer, maleic anhydride grafted hydrogenated styrene elastomer, filler and additives, and then melt-extruded at a temperature of 170 to 250° C. to obtain a nylon encapsulated TPE composite material. 9. Use of the nylon coated TPE composite material according to any one of claims 1 to 7 in the coating of power tool handles, game controllers and automotive parts. 10. A rubber-coated nylon product, comprising a nylon matrix and a coating agent coated on the surface of the nylon matrix, characterized in that the coating agent is the nylon rubber-coated TPE composite material according to any one of claims 1 to 7.