CN102311603A

CN102311603A - Calcium sulfate whisker modified polymethylmethacrylate and preparation process thereof

Info

Publication number: CN102311603A
Application number: CN201110106726A
Authority: CN
Inventors: 刘珍如; 刘立文; 付桃梅; 杨志强; 宁勇; 鲁纪鸣
Original assignee: 刘立文
Current assignee: Hunan Fu Xiang New Type Building Material Co ltd
Priority date: 2011-04-27
Filing date: 2011-04-27
Publication date: 2012-01-11
Anticipated expiration: 2031-04-27
Also published as: CN102311603B

Abstract

一种硫酸钙晶须改性聚甲基丙烯酸甲酯及其制备工艺，该硫酸钙晶须改性聚甲基丙烯酸甲酯由以下重量份数的原料制成：聚甲基丙烯酸甲酯74～84份，直径10～20μm的硫酸钙晶须15～25份，硬脂酸钙0.5～1.5份，PE蜡0～0.5份，四季戊四醇酯0.2～0.6份，亚磷酸酯0～0.2份。其制备方法是，将重量配比的各原料，在高速混合机中混合8～12min；将所得混合物通过同向平行双螺杆挤出机熔融挤出、造粒；再将所得粒料在同向平行双螺杆注塑机中注塑成型，即得。本发明之硫酸钙晶须改性聚甲基丙烯酸甲酯流动性好，抗冲击强度高，易于加工成型，特别适于制作对强度要求高的产品。A calcium sulfate whisker-modified polymethyl methacrylate and a preparation process thereof. The calcium sulfate whisker-modified polymethyl methacrylate is made of the following raw materials in parts by weight: polymethyl methacrylate 74- 84 parts, 15-25 parts of calcium sulfate whiskers with a diameter of 10-20 μm, 0.5-1.5 parts of calcium stearate, 0-0.5 parts of PE wax, 0.2-0.6 parts of tetraerythritol ester, and 0-0.2 part of phosphite. The preparation method is as follows: mix the raw materials in the weight ratio in a high-speed mixer for 8-12 minutes; melt and extrude the obtained mixture through a parallel twin-screw extruder in the same direction, and granulate; Injection molding in a parallel twin-screw injection molding machine to obtain. The calcium sulfate whisker-modified polymethyl methacrylate of the present invention has good fluidity, high impact strength, and is easy to process and shape, and is especially suitable for making products requiring high strength.

Description

A kind of calcium sulfate whisker modified polymethylmethacrylate and preparation technology thereof

Technical field

The present invention relates to a kind of polymethylmethacrylate and preparation technology thereof, relate in particular to a kind of calcium sulfate whisker modified polymethylmethacrylate and preparation technology thereof.

Background technology

Polymethylmethacrylate (PMMA) is commonly called as synthetic glass, acrylic or acryl, and its transparency is high, and transmittance reaches more than 92%, with the dyestuff good color development effect that stained.PMMA has application more widely in industries such as aviation, automobile, electronics, medical treatment, chemical industry, building materials, bathroom and Advertisement labels.

But existing PMMA material extensibility is lower, is prone to split, frangible, has limited its further application.

Summary of the invention

The technical problem that the present invention will solve is, overcomes the deficiency of existing polymethyl methacrylate materials, and a kind of good fluidity, calcium sulfate whisker modified polymethylmethacrylate and preparation technology thereof excellent in cushion effect are provided.

The present invention solve the technical problem the technical scheme that is adopted:

The present invention's calcium sulfate whisker modified polymethylmethacrylate is processed by the raw material of following parts by weight: 74～84 parts of polymethylmethacrylates (PMMA); 15～25 parts of the calcium sulfate crystal whiskers of diameter 10～20 μ m; 0.5～1.5 part of calcium stearate; 0～0.5 part of polyethylene wax (PE wax) (preferred 0.2 part), 0.2～0.6 part of pentaerythritol tetrathioglycollate, 0～0.2 part of phosphorous acid ester (preferred 0.1 part).

Preferred weight proportion is: 79 parts of polymethylmethacrylates (PMMA), 20 parts of the calcium sulfate crystal whiskers of diameter 10～20 μ m, 0.5 part of calcium stearate, 0.2 part in PE wax, 0.2 part of pentaerythritol tetrathioglycollate, 0.1 part of phosphorous acid ester.

The preparation technology of the present invention's calcium sulfate whisker modified polymethylmethacrylate comprises the steps:

The polymethylmethacrylate that (1) will take by weighing by the predetermined weight proportioning, calcium sulfate crystal whiskers, calcium stearate, polyethylene wax, pentaerythritol tetrathioglycollate, phosphorous acid ester add and mix 8～12min (preferred 10min) in the high-speed mixer, the mixture of polymethylmethacrylate, calcium sulfate crystal whiskers, calcium stearate, polyethylene wax, pentaerythritol tetrathioglycollate and phosphorous acid ester;

(2) step (1) gained mixture is melt extruded through the cocurrent and parallel twin screw extruder, granulation, processing parameter is following: a district temperature 185-195 ℃ (preferred 190 ℃); Two district temperature 190-200 ℃ (preferred 195 ℃); Three district temperature 195-205 ℃ (preferred 200 ℃), four district temperature 200-210 ℃ (preferred 205 ℃), five district temperature 210-220 ℃ (preferred 215 ℃); Six district temperature 220-230 ℃ (preferred 225 ℃); Seven district temperature 210-220 ℃ (preferred 215 ℃), melt temperature 210-220 ℃ (preferred 215 ℃), head temperature 200-210 ℃ (preferred 205 ℃); Residence time 3-5min (preferred 4min), pressure 3-6MPa (preferred 5Mpa);

(3) with the injection moulding in cocurrent and parallel twin screw injection moulding machine of step (2) gained pellet; The Shooting Technique parameter is following: 215-225 ℃ of nozzle temperature (preferred 220 ℃); One section temperature 220-230 ℃ (preferred 225 ℃); Two sections temperature 210-220 ℃ (preferred 215 ℃), injection pressure 90-110Mpa (preferred 100Mpa).

Calcium sulfate crystal whiskers is claimed crystal whisker of gypsum again, is a kind of fibrous single crystal of calcium sulfate.Research shows that the wastewaters with modified calcium sulfate whiskers length-to-diameter ratio of the present invention's use is 100, and diameter is 10～20 μ m, and it has uniform cross-sectional area, and complete internal structure, this characteristic are given its intensity near valence link between crystal theoretical value-atom.Because it has high intensity, trickle size is prone to and the PMMA interfacial adhesion; Improve consistency and interface cohesive force with matrix; When receiving the foreign compulsion orientation, the unrelieved stress among the PMMA can pass to calcium sulfate crystal whiskers well, thereby improves the intensity of matrix material; Because calcium sulfate crystal whiskers is an inorganics, in PMMA matrix, be uniformly dispersed, be difficult for reuniting, make composite property stable.

The present invention's calcium sulfate whisker modified polymethylmethacrylate, good fluidity, excellent in cushion effect is easy to machine-shaping, is particularly suitable for making the product high to requirement of strength.

Embodiment

Below in conjunction with embodiment the present invention is done further explain.

The raw material weight proportioning of the calcium sulfate whisker modified polymethylmethacrylate of embodiment 1-3 is seen table 1.

The preparation method of the calcium sulfate whisker modified polymethylmethacrylate of each embodiment:

The polymethylmethacrylate that (1) will take by weighing by the predetermined weight proportioning, calcium sulfate crystal whiskers, calcium stearate, PE wax, pentaerythritol tetrathioglycollate, phosphorous acid ester add in the high-speed mixer and mix 10min;

(2) each raw mix of step (1) gained is put into the loading hopper of cocurrent and parallel twin screw extruder, melt extruded, granulation, processing parameter is following: 190 ℃ of district's temperature, 195 ℃ of two district's temperature; 200 ℃ of three district's temperature, 205 ℃ of four district's temperature, 215 ℃ of five district's temperature; 225 ℃ of six district's temperature, 215 ℃ of seven district's temperature, 215 ℃ of melt temperatures; 205 ℃ of head temperatures, residence time 4min, pressure 5Mpa;

(3) with the injection moulding in cocurrent and parallel twin screw injection moulding machine of step (2) gained pellet, the Shooting Technique parameter is following: 220 ℃ of nozzle temperature, 225 ℃ of one section temperature, 215 ℃ of two sections temperature, injection pressure 100Mpa.

The product of embodiment 1-3 preparation is detected its performance according to ASTM examination criteria prescriptive procedure, and the result lists in table 2.

Figure 201110106726X100002DEST_PATH_IMAGE002

Claims

1. A calcium sulfate whisker modified polymethyl methacrylate, characterized in that it is made of the following raw materials in parts by weight: 74 to 84 parts of polymethyl methacrylate, calcium sulfate crystals with a diameter of 10 to 20 μm 15-25 parts of whiskers, 0.5-1.5 parts of calcium stearate, 0-0.5 parts of polyethylene wax, 0.2-0.6 parts of tetraerythritol ester, and 0-0.2 parts of phosphite.

2. calcium sulfate whisker modified polymethyl methacrylate according to claim 1, is characterized in that, described PE wax parts by weight are 0.2 part.

3. calcium sulfate whisker modified polymethyl methacrylate according to claim 1, is characterized in that, described phosphorous acid ester parts by weight are 0.1 part.

4. calcium sulfate whisker modified polymethyl methacrylate according to claim 1, is characterized in that, is made of the raw material of following parts by weight: polymethyl methacrylate 79 parts, diameter 10～20 μ m 20 parts of calcium sulfate whiskers, 0.5 parts of calcium stearate, 0.2 parts of PE wax, 0.2 parts of tetraerythritol ester, and 0.1 part of phosphite.

5. a preparation process of calcium sulfate whisker modified polymethyl methacrylate as claimed in one of claims 1 to 4, is characterized in that, comprises the following steps:

(1) Add polymethyl methacrylate, calcium sulfate whiskers, calcium stearate, polyethylene wax, tetraerythritol ester, and phosphite weighed according to a predetermined weight ratio into a high-speed mixer and mix for 8 to 12 minutes. A mixture of polymethyl methacrylate, calcium sulfate whiskers, calcium stearate, polyethylene wax, tetraerythritol ester and phosphite;

(2) Melt and extrude the mixture obtained in step (1) through a co-rotating parallel twin-screw extruder, and granulate. The process parameters are as follows: the temperature of the first zone is 185-195°C, the temperature of the second zone is 190-200°C, and the temperature of the third zone is 195 -205°C, the temperature of the fourth zone is 200-210°C, the temperature of the fifth zone is 210-220°C, the temperature of the sixth zone is 220-230°C, the temperature of the seventh zone is 210-220°C, the melt temperature is 210-220°C, and the temperature of the die head is 200-210°C ℃, residence time 3-5min, pressure 3-6MPa;

(3) Inject the pellets obtained in step (2) into a co-rotating parallel twin-screw injection molding machine. The injection molding process parameters are as follows: nozzle temperature 215-225°C, first stage temperature 220-230°C, second stage temperature 210-220°C , injection pressure 90-110Mpa.

6. a preparation technology of calcium sulfate whisker modified polymethyl methacrylate as claimed in claim 5, is characterized in that, comprises the following steps:

In the step (1), add polymethyl methacrylate, calcium sulfate whiskers, calcium stearate, polyethylene wax, tetraerythritol ester, and phosphite weighed according to a predetermined weight ratio into a high-speed mixer and mix 10min;

In the step (2), the melt extrusion process parameters are as follows: the temperature of the first zone is 190°C, the temperature of the second zone is 195°C, the temperature of the third zone is 200°C, the temperature of the fourth zone is 205°C, the temperature of the fifth zone is 215°C, the temperature of the sixth zone is 225°C, The temperature in the seventh zone is 215°C, the melt temperature is 215°C, the head temperature is 205°C, the residence time is 4min, and the pressure is 5MPa;

In the step (3), the injection molding process parameters are as follows: the nozzle temperature is 220°C, the first stage temperature is 225°C, the second stage temperature is 215°C, and the injection pressure is 100MPa.