CN108164819A - Nanotube galapectite-diatomite-polymer micro-nano composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a nanotube halloysite-diatomite-polymer micro-nano composite material and a preparation method thereof. The micro-nano composite material is composed of spray-granulated halloysite-diatomite mixture and polymer Any one of the powders in PP and PA6 is mixed and made into halloysite-diatomite-polymer micro-nano composite powder by high-speed pulverization, and then made by twin-screw extrusion molding. The tensile strength of the prepared composite material is Strength increased by 12‑16%, Young's modulus relative elastic modulus increased by 38‑50%, flexural strength increased by 20‑46%, notched impact strength increased by 30‑43%, Rockwell hardness increased by 6 -12%. The present invention does not need surface modification, and only by adjusting the different ratios of halloysite and diatomaceous earth, the performance of the enhanced polymer is realized; the preparation process is simple, there is no environmental pollution, it can be produced in large quantities, and the cost is low; the mechanical properties of the filled composite are improved. overall enhancement.

Description

Nanotube halloysite-diatomite-polymer micro-nano composite material and preparation method thereof

technical field

The invention belongs to the field of macromolecules, and relates to a preparation method of halloysite-diatomite-polymer micro-nano composite material.

Background technique

Polymer nanocomposites are new materials filled with nano fillers, which have better thermal and physical properties than conventional polymer materials. Polypropylene (PP and PA6) has become one of the widely used thermoplastic polymers in household goods, auto parts, electronic packaging, etc., due to its low processing cost and high resistance to crack opening, but very low crack growth resistance, especially Its impact resistance is quite poor at low temperatures. Therefore, polymers tend to be used in combination with various nanofillers, such as carbon nanotubes, layered silicates (montmorillonite), and nanoparticles (silicon dioxide, graphite, calcium carbonate, etc.). When the inorganic additives are sufficiently dispersed in the polymer, the mechanical properties of the polymer can be improved.

Demori et al. found that non-ionic surfactant-based propoxylated and ethoxylated alkylphenols as plasticizers also increased the dispersion of HNTs (Hallosite), and the resulting nanocomposites did not lose impact strength. Under the premise of thermal performance, it shows an increase in Young's modulus [AIP Conference Proceedings, 2014, 274: 1593]. Ismail et al. studied the effect of HNTs on the performance of PP composite materials, and concluded that under the load of 2% HNTs, the composite material showed a 22% increase in tensile strength, although the elongation at break was slightly reduced, but the modulus and rigidity Increased, and improved thermal stability [Journal of Vinyl & Additive Technology, 2016, 22:487-491]. Erdogan et al. used a silane coupling agent (γ-aminopropyltriethoxysilane (APTES)) to modify HNTs to fill PA6, and the yield strength, tensile strength and flexural strength of the nanocomposite were increased by 22%, 21% and 41% [Polymer Composites, 2014, 35:1350-1361].

The above research results show that the surface modification of halloysite is necessary to obtain better performance by filling halloysite alone into the polymer. In addition, from the effect of filling, although some properties of the polymer are enhanced indicators, but it will also lead to the decline of other indicators. The whole preparation process is complicated to operate, the cost is high, and there is a risk of environmental pollution.

Contents of the invention

The invention aims to provide a preparation method of halloysite-diatomite-polymer micro-nano composite material.

The technical solution that realizes the object of the present invention is:

A nanotube halloysite-diatomite-polymer micro-nano composite material, which is made of spray-granulated halloysite-diatomite mixture mixed with any powder of polymer PP and PA6, and then pulverized at a high speed The halloysite-diatomite-polymer micro-nano composite powder is made by twin-screw extrusion molding.

Further, the mixed mixture of halloysite and diatomite accounts for 5-8% of the total weight of the composite material.

Further, the tensile strength of the composite material is increased by 12-16%, the relative elastic modulus of Young's modulus is increased by 38-50%, the bending strength is increased by 20-46%, and the notched impact strength is increased by 30%. -43%, Rockwell hardness was improved by 6-12%.

The preparation method of above-mentioned composite material, comprises the steps:

(1) First sieve the natural halloysite and diatomite powder with a 100-200 mesh sieve, then put the above two sieved powders into a container according to a certain proportion, and pour in 2-4 times its volume Dry ice or liquid nitrogen, then dry at 100-120°C for 3-6 hours;

(2) Add the above dried filler to 1mol/L sodium hydroxide solution according to the weight ratio 1:(2-5), adjust the pH=10-12, stir the temperature at 30-60°C, process for 4-6 hours, filter and Washing to prepare a suspension liquid with a solid content of 20-50wt.%.

(3) The suspension liquid in step (2) is granulated by spray drying, the inlet temperature is 140-160°C; the outlet temperature is 70-80°C, and the pressure is 0.2-0.4MPa;

(4) Put the spray-granulated halloysite-diatomite and polymer powder into a high-speed powder machine for 1-3 hours, and the speed of the powder machine is 1000-3000r/min to prepare halloysite -Diatomite-polymer micro-nano composite powder;

(5) The micro-nano composite material powder described in step (4) is prepared into a nanotube halloysite-diatomite-polymer composite material with a twin-screw extruder, wherein the screw speed of the extruder is 80- 100r/min, preheating temperature 140-180℃, the temperature from the hopper to the mold is (140-160)/(180-200)/(180-200)/(200-220)/(200-220)/ (200-220)/(200-220)°C.

Further, in step (1), the weight ratio of halloysite and diatomaceous earth is (1-6):(6-1).

Further, in step (1), the diatomaceous earth is a disc-shaped macroporous structure with a diameter of 4-6 microns, and the macropore diameter is 40-60 nanometers; the halloysite has a diameter of 50-80 nanometers and a length of A hollow tubular structure of 1-3 microns.

Further, in step (3), the particle size of the spray-dried granulation is 100-500 microns, preferably 100-300 microns.

Further, in step (3), two-fluid spray drying equipment is used for spray drying.

Further, in step (4), the polymer is one of PP and PA6.

Compared with the prior art, the present invention has the advantages of: (1) halloysite and diatomite are used as natural mineral nanomaterials, which are safe and environmentally friendly, and the raw materials are easy to get, and the price is far lower than carbon nanotubes and carbon fibers; The surface modification realizes the enhanced performance of the polymer only by adjusting the different ratios of halloysite and diatomaceous earth. (3) The preparation process is simple, no environmental pollution, mass production is possible, and the cost is low. (4) The mechanical properties of the filled composites are fully improved.

Description of drawings

Fig. 1 is a cross-sectional morphology diagram of the samples described in Example 2 (A) and Example 5 (B) of the present invention.

Detailed ways

Example 1

Use a 100-mesh sieve to sieve natural halloysite and diatomaceous earth powder, pour liquid nitrogen twice its volume, and dry in an oven at 110°C for 4 hours, then take 1 part by weight of halloysite and diatomaceous earth powder. Mix 6 parts of the soil evenly with a high-speed powder machine at a speed of 1000r/min. After taking it out, add 1mol/L sodium hydroxide solution twice its weight to it, adjust the pH to 11, and the stirring temperature to 50°C. After 3 hours, filter and wash 5 times, add distilled water and stir to dilute to become a 40wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 140°C; the outlet temperature to 80°C and the pressure to 0.3MPa, and implement spray granulation. The average particle size after granulation is 400 microns. Take 94 parts by weight of the PP masterbatch, the above-mentioned granules are 6 parts by weight, pour them into the powder material machine for treatment for 1 hour, and the speed is 2000r/min, and finally the halloysite-diatomite-PP is obtained Polymer micro-nano composite powder. The micro-nano composite material powder was prepared into the halloysite-diatomite-PP polymer composite material with a twin-screw extruder, the screw speed was 100r/min, the preheating temperature was 160°C, and the temperatures from the hopper to the mold were respectively : 150/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 1.

Example 2

Use a 100-mesh sieve to sieve natural halloysite and diatomaceous earth powder respectively, pour into dry ice that is 4 times its volume, and after drying in an oven at 120°C for 6 hours, take 3 parts by weight of halloysite and silica Mix 3 parts of algae earth evenly with a high-speed powder machine at a speed of 1000r/min, add the mixed mixture to a 1mol/L sodium hydroxide solution twice its weight, adjust the pH to 10, and stir at 40°C , and the treatment time was 4 hours. After filtering and washing for 3 times, distilled water was added to stir and dilute to become a suspension liquid of 40wt.%. Adjust the inlet temperature of the spray drying equipment to 150°C; the outlet temperature to 80°C and the pressure to 0.3MPa, and implement spray granulation, and the average particle size of the granulated mixture is 300 microns. Take 94 parts by weight of PP masterbatch, the above-mentioned granulation mixture is 6 parts by weight, pour it into the powder material machine for 3 hours, and the rotation speed is 1000r/min, and finally the halloysite-diatomite- PP micro-nano composite powder. The micro-nano composite material powder is prepared into a nanotube halloysite-diatomite-PP polymer composite material with a twin-screw extruder, the screw speed is 100r/min, the preheating temperature is 140°C, and the temperature from the hopper to the mold They are: 140/200/200/220/220/220/220°C. The mechanical properties of the samples are listed in Table 1, and the cross-sectional photos are shown in Figure 1(A).

Example 3

Use a 200-mesh sieve to sieve natural halloysite and halloysite powder, pour liquid nitrogen twice its volume, and dry in an oven at 120°C for 3 hours, then take 6 parts by weight of halloysite and silicon Mix 1 part of algae earth evenly with a high-speed powder machine at a speed of 1000r/min, take it out and add it to a 1mol/L sodium hydroxide solution that is three times its weight, adjust the pH to 10, and the stirring temperature to 40°C. After 4 hours, filter and wash 3 times, add distilled water and stir to dilute to become a 30wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 145°C; the outlet temperature to 75°C and the pressure to 0.2MPa, and implement spray granulation. The average particle size after granulation is 300 microns. Take 94 parts by weight of PP masterbatch, the above-mentioned granules are 6 parts by weight, pour them into the powder material machine for 1 hour, and the rotation speed is 2000r/min, and finally the halloysite-diatomite-PP micro-nano Composite powder. The micro-nano composite material powder was prepared into the halloysite-diatomite-PP polymer composite material with a twin-screw extruder, the screw speed was 100r/min, the preheating temperature was 160°C, and the temperatures from the hopper to the mold were respectively : 150/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 1.

Example 4

Use a 100-mesh sieve to sieve the natural halloysite and diatomite powder, pour it into dry ice that is 4 times its volume, and dry it in an oven at 100°C for 3 hours, then take 1 part by weight of halloysite and diatomaceous earth powder. Mix 6 parts of soil evenly with a high-speed powder machine at a speed of 1000r/min, take it out and add it to a 1mol/L sodium hydroxide solution twice its weight, adjust the pH to 10, stir at 60°C, and process for After 3 hours, filter and wash 3 times, add distilled water and stir to dilute to become a 30wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 140°C; the outlet temperature to 80°C and the pressure to 0.3MPa, and implement spray granulation. The average particle size after granulation is 400 microns. Take 94 parts by weight of the PA6 masterbatch, the above-mentioned granules are 6 parts by weight, pour it into the powder material machine for processing for 1 hour, and the rotating speed is 2000r/min, and finally halloysite-diatomite-PA6 is obtained Polymer micro-nano composite powder. The micro-nano composite material powder is prepared into halloysite-diatomite-PA6 polymer composite material with a twin-screw extruder, the screw speed is 100r/min, the preheating temperature is 160°C, and the temperatures from the hopper to the mold are respectively : 150/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 2.

Example 5

Use a 100-mesh sieve to sieve the natural halloysite and diatomite powder respectively, pour into dry ice that is 4 times its volume, and after drying in an oven at 110°C for 3 hours, take 5 parts by weight of halloysite and silica Mix 1 part of algae earth evenly with a high-speed powder machine at a speed of 1000r/min. After taking it out, add the mixture to a 1mol/L sodium hydroxide solution that is three times its weight, adjust the pH to 11, and stir at 50°C. The treatment time was 4 hours. After filtering and washing for 3 times, distilled water was added to stir and dilute to become a 32 wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 160°C; the outlet temperature to 70°C and the pressure to 0.3MPa, and implement spray granulation. The average particle size of the granulated mixture is 200 microns. Take 95 parts by weight of PA6 masterbatch, the above-mentioned granulation mixture is 5 parts by weight, pour it into the powder material machine for 3 hours, and the rotation speed is 1000r/min, and finally the halloysite-diatomite- PA6 polymer micro-nano composite powder. The micro-nano composite material powder is prepared into a nanotube halloysite-diatomite-PA6 composite material with a twin-screw extruder, the screw speed is 100r/min, the preheating temperature is 140°C, and the temperatures from the hopper to the mold are respectively : 140/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 2, and the cross-sectional photos are shown in Figure 1(B).

Example 6

Use a 100-mesh sieve to sieve natural halloysite and diatomite powder, pour liquid nitrogen three times its volume, and dry in an oven at 120°C for 4 hours, then take 6 parts by weight of halloysite and silicon Mix 1 part of algae earth evenly with a high-speed powder machine at a speed of 1000r/min, take it out and add it to a 1mol/L sodium hydroxide solution that is three times its weight, adjust the pH to 11, and the stirring temperature to 60°C. After 6 hours, filter and wash 3 times, add distilled water and stir to dilute to become a 36wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 150°C; the outlet temperature to 75°C and the pressure to 0.3MPa, and implement spray granulation. The average particle size after granulation is 300 microns. Take 94 parts by weight of the PA6 masterbatch, the above-mentioned granules are 6 parts by weight, pour it into the powder material machine for processing for 1 hour, and the rotating speed is 2000r/min, and finally halloysite-diatomite-PA6 is obtained Micro-nano composite powder. The micro-nano composite material powder was prepared into the halloysite-diatomite-PA6 polymer composite material with a twin-screw extruder, the screw speed was 100r/min, the preheating temperature was 140°C, and the temperatures from the hopper to the mold were : 160/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 2.

Comparative example 1

Sieve the diatomite powder with a 100-mesh sieve, pour dry ice twice its volume, and dry it in an oven at 110°C for 4 hours, then add 1mol/L sodium hydroxide solution that is twice its weight In the process, the pH was adjusted to 11, the stirring temperature was 50°C, and the treatment time was 3 hours. After filtering and washing for 5 times, distilled water was added to stir and dilute to become a 40wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 140°C; the outlet temperature to 80°C and the pressure to 0.3MPa, and implement spray granulation. The average particle size after granulation is 400 microns. Take 94 parts of PP masterbatch, the number of the above-mentioned granules is 6 parts, and pour it into a powder feeder for processing for 1 hour at a speed of 2000r/min, and finally obtain diatomite-PP micro-nano composite powder. The micro-nano composite material powder was prepared into a nanotube halloysite-diatomite-polymer composite material with a twin-screw extruder, the screw speed was 100r/min, the preheating temperature was 160°C, and the temperatures from the hopper to the mold were respectively For: 150/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 1.

Comparative example 2

Sieve the halloysite powder with a 200-mesh sieve, pour liquid nitrogen twice its volume, and dry it in an oven at 120°C for 3 hours, then add it to a 1mol/L sodium hydroxide solution that is three times its weight. The pH was adjusted to 10, the stirring temperature was 40° C., and the treatment time was 4 hours. After filtering and washing for 3 times, distilled water was added to stir and dilute to become a 30 wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 145°C; the outlet temperature to 75°C and the pressure to 0.4MPa, and implement spray granulation. The average particle size after granulation is 300 microns. Take 94 parts of PP masterbatch, and the number of granules above is 6 parts, pour it into the powder feeder for 1 hour, and the rotation speed is 1000r/min, and finally prepare the halloysite-diatomite-PP micro-nano composite powder . The micro-nano composite material powder is prepared into a nanotube halloysite-polymer composite material with a twin-screw extruder, the screw speed is 100r/min, the preheating temperature is 160°C, and the temperatures from the hopper to the mold are: 150/ 200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 1.

Comparative example 3

Use a 200-mesh sieve to sieve the diatomaceous earth powder, pour dry ice that is three times the volume, and dry it in an oven at 100°C for 3 hours, then add 1mol/L sodium hydroxide solution that is four times its weight In the process, the pH was adjusted to 10, the stirring temperature was 70°C, and the treatment time was 3 hours. After filtering and washing 5 times, distilled water was added to stir and dilute to become a 40wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 130°C; the outlet temperature to 70°C and the pressure to 0.2MPa, and implement spray granulation. The average particle size after granulation is 500 microns. Take 94 parts of PA6 masterbatch, the number of parts of the above granules is 6 parts, pour it into a powder feeder for treatment for 1 hour, and the rotation speed is 1000r/min, and finally obtain diatomite-PA6 micro-nano composite powder. The micro-nano composite material powder was prepared into a nanotube halloysite-diatomite-polymer composite material with a twin-screw extruder, the screw speed was 100r/min, the preheating temperature was 160°C, and the temperatures from the hopper to the mold were respectively For: 150/200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 2.

Comparative example 4

Sieve the halloysite powder with a 100-mesh sieve, pour liquid nitrogen that is 4 times its volume, and dry it in an oven at 110°C for 5 hours, then add it to a 1mol/L sodium hydroxide solution that is twice its weight. The pH was adjusted to 9, the stirring temperature was 50° C., and the treatment time was 2 hours. After filtering and washing for 3 times, distilled water was added to stir and dilute to become a 30 wt.% suspension liquid. Adjust the inlet temperature of the spray drying equipment to 145°C; the outlet temperature to 85°C and the pressure to 0.1MPa, and implement spray granulation. The average particle size after granulation is 400 microns. Take 94 parts of PA6 masterbatch, 6 parts of the above-mentioned granules, pour it into the powder feeder for 1 hour, and the rotation speed is 2000r/min, and finally prepare the halloysite-diatomite-PA6 micro-nano composite powder . The micro-nano composite material powder is prepared into a nanotube halloysite-polymer composite material with a twin-screw extruder, the screw speed is 100r/min, the preheating temperature is 160°C, and the temperatures from the hopper to the mold are: 150/ 200/200/220/220/220/220°C, the mechanical properties of the samples are listed in Table 1.

Table 1 Mechanical properties of halloysite-diatomite-PP micro-nano composites

Table 2 Mechanical properties of halloysite-diatomite-PA6 micro-nano composites

Note: (1) When determining the tensile strength of the yield, the parallel head speed of stretching is 100mm/min, and the tensile strength, modulus and elongation at break of the composite material can be obtained directly from the recorded stress-strain curve, A double-shovel-type (bone-shaped sample) sample is 115 mm long, 10.20 mm wide, and 4.24 mm thick; (2) relative modulus refers to the ratio of the Young's modulus of the embodiment to the blank sample. Experimental Flexural strength was determined by a three-point bending test. The bending crosshead speed is 5mm/min, the span is 64mm, and the width and thickness of the bent sample are about 10.20mm and 4.24mm. (3) The notched impact strength of the notched impact specimen. The dimensional parameters of each sample were measured by a digital micrometer. Each sample is tested at least five times, and all data are shown as the average value and standard deviation) (5) The Rockwell hardness test process is: use the specified R-type indenter, first apply the initial test force (large pointer), and then apply the main force Test force (small pointer), and then return to the initial test force, the Rockwell hardness of the material is expressed by the depth difference of the sample under the two test forces before and after the application of force. The hardness of the sample was measured with an XHRD-150 Rockwell hardness tester; (6) The data was the average value of 5 parallel experiments.

Claims (10)

1. Nanotube halloysite-diatomite-polymer micro-nano composite material, characterized in that, the mixture of halloysite-diatomite mixture sprayed and granulated is mixed with any powder in polymer PP and PA6 Afterwards, the halloysite-diatomite-polymer micro-nano composite powder is made by high-speed crushing, and then it is made by twin-screw extrusion molding. 2. composite material as claimed in claim 1, is characterized in that, halloysite and diatomite mixed mixture account for 5-8% of composite material gross weight. 3. composite material as claimed in claim 1, is characterized in that, the tensile strength of described composite material has increased 12-16%, and the relative elastic modulus of Young's modulus has increased 38-50%, and flexural strength Increased by 20-46%, notched impact strength increased by 30-43%, Rockwell hardness increased by 6-12%. 4. The preparation method of nanotube halloysite-diatomite-polymer micro-nano composite material, is characterized in that, comprises the steps: (1) Sieve natural halloysite and diatomaceous earth powder according to a certain ratio, put them into a container, pour dry ice or liquid nitrogen, and dry at 100-120°C for 3-6 hours; (2) Add the dried filler in step (1) to sodium hydroxide solution, adjust pH=10-12, stir at 30-60°C, process for 4-6 hours, filter and wash, and prepare a solid content of 20-50wt. % suspension liquid; (3) The suspension liquid in step (2) is granulated by spray drying, the inlet temperature is 140-160°C; the outlet temperature is 70-80°C, and the pressure is 0.2-0.4MPa; (4) The spray granulated halloysite-diatomite and polymer powder are crushed at high speed for 1-3 hours to prepare the halloysite-diatomite-polymer micro-nano composite powder; (5) The micro-nano composite material powder described in step (4) is prepared into a nanotube halloysite-diatomite-polymer composite material with a twin-screw extruder, wherein the screw speed of the extruder is 80- 100 r/min, preheating temperature 140-180 ℃, the temperature from the hopper to the mold is (140-160)/(180-200)/(180-200)/(200-220)/(200-220) /(200-220)/(200-220)℃. 5. preparation method as claimed in claim 4 is characterized in that, natural halloysite and diatomite powder are sieved with 100-200 mesh sieve. 6. preparation method as claimed in claim 4 is characterized in that, dry ice or liquid nitrogen are 2-4 times of natural halloysite and diatomite powder volume. 7. preparation method as claimed in claim 4, is characterized in that, the weight ratio of natural halloysite and diatomite is (1-6): (6-1). 8. preparation method as claimed in claim 4 is characterized in that, diatomaceous earth is the disc shape macroporous structure that diameter is 4-6 micron, and macropore aperture 40-60 nanometer; Natural halloysite is that diameter is 50 - 80 nm, hollow tubular structures with a length of 1-3 microns. 9. The preparation method according to claim 4, characterized in that, the filler dried in step (1) is added to 1mol/L sodium hydroxide solution in a weight ratio of 1:(2-5). 10. The preparation method according to claim 4, wherein the high-speed pulverization process adopts a high-speed pulverizer, and the speed of the powder machine is 1000-3000r/min.