CN110607063A - PC/PMMA composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a PC/PMMA composite material and a preparation method thereof, wherein PP-g-St is taken as a compatilizer, and is blended and extruded with PC and PMMA to synthesize the PC/PMMA composite material, and the PC/PMMA composite material comprises the following components in percentage by weight: 50-90% of PC, 4-20% of PMMA, 4-30% of PP-g-St and 2% of organic silicon light diffusant. The preparation method comprises the following steps: step 1: weighing the materials according to the weight percentage and uniformly mixing to obtain a PC/PMMA mixed material; step 2: feeding the mixed material into a double-screw extruder for extrusion granulation to obtain the PC/PMMA composite material, wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 226-230 ℃; and a second zone: 236-240 ℃; and (3) three zones: 246 ℃ and 250 ℃; and (4) four areas: 246 ℃ and 250 ℃; and a fifth zone: 252-256 ℃; a sixth zone: 257 ℃ and 261 ℃; seven areas: 246 ℃ and 250 ℃; and eight regions: 226-230 ℃; nine zones 176-180 ℃. The method can enhance the physical properties of the material and effectively improve the tensile strength, surface hardness, heat distortion temperature and glossiness of the material.

Description

PC/PMMA composite material and preparation method thereof

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a PC/PMMA composite material and a preparation method thereof.

Background

Polycarbonate (PC) is a thermoplastic with excellent properties, is colorless and transparent, has good heat resistance, strong impact resistance and good dimensional stability, and has good mechanical properties at common use temperatures. However, they have disadvantages such as insufficient fluidity, poor chemical resistance, poor stress cracking resistance, and poor balance between surface hardness and toughness during processing.

Polymethyl methacrylate (PMMA) is relatively inexpensive to PC, and when blended with PC, it can improve the abrasion resistance, solvent resistance and processability of PC. However, the compatibility between PC and PMMA is poor, and how to solve the problem of poor compatibility between PC and PMMA becomes the research direction of those skilled in the art.

Disclosure of Invention

The invention aims to provide a PC/PMMA composite material with high hardness, good mechanical stability, good chemical resistance and scratch-resistant surface and a preparation method thereof.

In order to achieve the purpose, the invention adopts the following technical scheme:

a PC/PMMA composite material is prepared by taking PP-g-St as a compatilizer, blending and extruding the compatilizer with PC and PMMA to synthesize the PC/PMMA composite material, and comprises the following components in percentage by weight: 50-90% of PC, 4-20% of PMMA, 4-30% of PP-g-St and 2% of organic silicon light diffusant.

Meanwhile, the invention also provides a preparation method of the compatilizer PP-g-St, which comprises the following steps:

adding an initiator and St into PP for premixing, adding into a double-screw extruder for extrusion and granulation after uniform mixing, wherein the weight average molecular weight of the synthesized PP-g-St is 30000-100000.

Wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 160. and a second zone: 180. and (3) three zones: 190. and (4) four areas: 190. and a fifth zone: 200. a sixth zone: 200. seven areas: 200. and eight regions: 210 and nine zones: at 210 ℃.

Wherein the rotating speeds of the main machine of the double-screw extruder and the feeding screw are respectively 120r/min and 20 r/min.

Wherein the addition amount of the initiator accounts for 0.5-3% of the total weight of the PP, and the addition amount of St accounts for 0.1-2.0% of the total weight of the PP.

Wherein the initiator is an azo initiator or an organic peroxide initiator. For example, azo initiator AIBN, organic peroxide initiator BPO, etc.

The invention also provides a preparation method of the PC/PMMA composite material, which comprises the following steps:

step 1: weighing the materials according to the weight percentage and uniformly mixing to obtain a PC/PMMA mixed material;

step 2: feeding the mixed material into a double-screw extruder for extrusion granulation to obtain the PC/PMMA composite material, wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 226-230 ℃; and a second zone: 236-240 ℃; and (3) three zones: 246 ℃ and 250 ℃; and (4) four areas: 246 ℃ and 250 ℃; and a fifth zone: 252-256 ℃; a sixth zone: 257 ℃ and 261 ℃; seven areas: 246 ℃ and 250 ℃; and eight regions: 226-230 ℃; nine zones 176-180 ℃.

Compared with the prior art, the invention has the beneficial effects that:

the invention takes Benzoyl Peroxide (BPO) as an initiator and styrene (Styrene, St) as a grafting monomer to modify polypropylene (PP) and synthesize a compatilizer, namely styrene grafted polypropylene (PP-g-St). The PC/PMMA composite material is obtained by adopting a limited PC and PMMA feeding ratio and PP-g-St as a compatilizer through twin-screw extrusion. The synthesized compatilizer PP-g-St has a main chain structure similar to that of PP and a branched chain structure similar to that of PMMA, so that the adhesive force between PC and PMMA is increased through the bonding force between molecules to form a stable structure, namely the PC/PMMA is compatible. The method can enhance the physical properties of the material and effectively improve the tensile strength, surface hardness, heat distortion temperature and glossiness of the material. The obtained PC/PMMA composite material can be widely applied to the fields of engineering materials, packaging, electronic display and the like. The compatibility of PC/PMMA can be effectively improved, the performance stability of the composite material is better, and the storage time and the service life of the material are prolonged.

Detailed Description

The present invention will be further described with reference to the following examples, which are intended to illustrate only some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, other embodiments used by those skilled in the art without any creative effort belong to the protection scope of the present invention.

Example 1

Adding 0.5 mass percent of BPO and 0.1 mass percent of St into PP, uniformly mixing in advance, adding into a double-screw extruder, extruding and granulating. The extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 160. and a second zone: 180. and (3) three zones: 190. and (4) four areas: 190. and a fifth zone: 200. a sixth zone: 200. seven areas: 200. and eight regions: 210 and nine zones: at 210 ℃. The rotating speeds of a main machine of the double-screw extruder and a feeding screw are 120r/min and 20r/min respectively. Extruding to obtain the compatilizer PP-g-St.

And weighing 1kg of materials according to the weight percentage of 40 percent of PC, 40 percent of PMMA, 18 percent of PP-g-St and 2 percent of organic silicon light diffusant, and uniformly mixing to obtain the PC/PMMA mixed material. Feeding the mixed material into a double-screw extruder for extrusion granulation to obtain the PC/PMMA composite material, wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 226 deg.C; and a second zone: 236 ℃; and (3) three zones: 246 ℃; and (4) four areas: 246 ℃; and a fifth zone: 252 ℃; a sixth zone: 257 ℃; seven areas: 246-DEG C; and eight regions: 226 deg.C; nine zones 176 ℃.

Example 2

Adding BPO with the mass fraction of 0.5% and St with the mass fraction of 2.0% into PP, uniformly mixing in advance, adding into a double-screw extruder, extruding and granulating. The extruder is divided into 9 sections, and the heating temperature of each section is respectively one zone: 160. and a second zone: 180. and (3) three zones: 190. and (4) four areas: 190. and a fifth zone: 200. a sixth zone: 200. seven areas: 200. and eight regions: 210 and nine zones: the rotating speeds of a main machine and a feeding screw of the double-screw extruder are 120r/min and 20r/min respectively at 210 ℃. Extruding to obtain the compatilizer PP-g-St.

And weighing 1kg of the materials according to the weight percentage of 65 percent of PC, 20 percent of PMMA, 13 percent of PP-g-St and 2 percent of organic silicon light diffusant, and uniformly mixing to obtain the PC/PMMA mixed material. And (2) feeding the mixed material into a double-screw extruder for extrusion granulation to obtain the PC/PMMA composite material, wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 230 ℃; and a second zone: 240 ℃; and (3) three zones: 250 ℃; and (4) four areas: 250 ℃; and a fifth zone: 256 ℃; a sixth zone: 261 deg.C; seven areas: 250 ℃; and eight regions: 230 ℃; nine zones 180 ℃.

The physical properties of the PC/PMMA composites obtained in the above two examples are shown in Table 1.

TABLE 1 physical Property parameters of PC/PMMA composites in examples 1 and 2

	Example 1	Example 2
			Impact Strength (J/m)	668	613
Tensile Strength (mPa)	63	57
			Heat distortion temperature (. degree. C.)	120	117
Surface hardness	4H	3H
			Surface gloss (%)	88	91

As can be seen from the above Table 1, the impact strength, tensile strength, heat distortion temperature, surface hardness and surface gloss of the PC/PMMA composite material obtained by the present invention are greatly improved compared with the conventional PC/PMMA composite material without the addition of the compatibilizer.

Although the present invention has been described herein with reference to the illustrated embodiments thereof, which are intended to be preferred embodiments of the present invention, it is to be understood that the invention is not limited thereto, and that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure.

Claims (7)

1. A PC/PMMA composite material is characterized in that: PP-g-St is taken as a compatilizer, and is blended and extruded with PC and PMMA to synthesize the PC/PMMA composite material, which comprises the following components in percentage by weight: 50-90% of PC, 4-20% of PMMA, 78-30% of PP-g-St4 and 2% of organic silicon light diffusant.

2. PC/PMMA composite according to claim 1, characterized in that the compatibilizer PP-g-St is prepared as follows:

adding an initiator and St into PP for premixing, adding into a double-screw extruder for extrusion and granulation after uniform mixing, wherein the weight average molecular weight of the synthesized PP-g-St is 30000-100000.

3. The PC/PMMA composite according to claim 2, wherein the twin screw extruder is divided into 9 sections, each section having a temperature setting range of: a first area: 160. and a second zone: 180. and (3) three zones: 190. and (4) four areas: 190. and a fifth zone: 200. a sixth zone: 200. seven areas: 200. and eight regions: 210 and nine zones: at 210 ℃.

4. The PC/PMMA composite according to claim 2, characterized in that the screw speeds of the main machine and the feeding of the twin-screw extruder are 120r/min and 20r/min, respectively.

5. The PC/PMMA composite according to claim 2, wherein the initiator is added in an amount of 0.5-3% by weight of the PP, and St is added in an amount of 0.1-2.0% by weight of the PP.

6. The PC/PMMA composite according to claim 2, wherein the initiator is an azo-type initiator or an organic peroxide-type initiator.

7. A method for preparing a PC/PMMA composite material, comprising the PC/PMMA composite material according to any one of claims 1 to 6, comprising the steps of:

step 1: weighing the materials according to the weight percentage and uniformly mixing to obtain a PC/PMMA mixed material;

step 2: feeding the mixed material into a double-screw extruder for extrusion granulation to obtain the PC/PMMA composite material, wherein the double-screw extruder is divided into 9 sections, and the temperature setting range of each section is as follows: a first area: 226-230 ℃; and a second zone: 236-240 ℃; and (3) three zones: 246 ℃ and 250 ℃; and (4) four areas: 246 ℃ and 250 ℃; and a fifth zone: 252-256 ℃; a sixth zone: 257 ℃ and 261 ℃; seven areas: 246 ℃ and 250 ℃; and eight regions: 226-230 ℃; nine zones 176-180 ℃.