CN103289340B - Transparent biodegradable composites of polypropylene carbonate/Sodium sulfate anhydrous.min(99) and preparation method thereof - Google Patents

Abstract

The present invention relates to the transparent biodegradable composites of a kind of polypropylene carbonate/Sodium sulfate anhydrous.min(99), its composition by weight is: polypropylene carbonate 60%-95%, Sodium sulfate anhydrous.min(99) 5%-40%, surface-modifying agent 0-1%, lubricant 0-0.5%.In the present invention, Sodium sulfate anhydrous.min(99) is cheap as stopping composition, and the refractive index of its refractive index and polypropylene carbonate closely, affects less on the transparency of goods after therefore carrying out compound with resin matrix; The oil number of Sodium sulfate anhydrous.min(99) is lower than conventional filler such as calcium carbonate, can reduce the usage quantity of other auxiliary agent in composite processing process, is conducive to the manufacturing cost reducing product.

Description

Polypropylene carbonate/sodium sulfate transparent fully degradable composite material and preparation method thereof

technical field

The invention relates to a transparent fully degradable composite material of polypropylene carbonate/salphin and a preparation method thereof, belonging to the field of preparation of composite materials combining inorganic powders and polymer materials.

Background technique

Environmental protection issues have attracted more and more attention from all over the world, and solving the "white pollution" problem caused by non-degradable polymer material waste has become the bounden duty of polymer material researchers. Polypropylene carbonate (PPC) is a new type of degradable aliphatic polycarbonate, which is obtained by alternating copolymerization of greenhouse gases carbon dioxide and propylene oxide under the action of a catalyst, so it is also called carbon dioxide fully degradable plastic. PPC has the advantages of excellent biodegradability, good transparency, high barrier and biocompatibility. In addition, because it uses carbon dioxide waste gas as a polymerization monomer, it is an effective means of comprehensive utilization of _CO2 . The synthesis and application of PPC has received widespread attention. In recent years, the polymerization technology of carbon dioxide fully degradable plastics has developed and improved rapidly. Chinese scholars occupy an important position in the world in the research of carbon dioxide fully degradable plastics. Its key technologies are at the international leading level. The industrialization process of carbon dioxide fully degradable plastics is advancing. faster. However, due to the disadvantages of PPC itself, such as poor heat resistance, low glass transition temperature, and high cost, it is greatly restricted when used as a structural material on a large scale. Therefore, physical or chemical modification of PPC is required to improve its mechanical properties. Performance and thermal performance, reducing the cost of its products is of great significance.

Inorganic powder filling is an important method for modifying polymer materials. It can reduce costs and improve certain physical or chemical properties. Commonly used inorganic powders such as calcium carbonate, talcum powder, mica powder, kaolin, etc. Sexual technology has been relatively mature. However, filling most traditional inorganic powders into polymers will lead to a significant decrease in the transparency of the product, and the product will become white and dirty. Therefore, it is impossible to use these traditional inorganic powders for filling modification for products that require high transparency. Anhydrous sodium sulfate is anhydrous sodium sulfate. It is colorless and transparent with large crystals or small granular crystals. It is one of the bulk products of the inorganic salt industry. Wide range of applications. Using sodium sulfate as a modified filler for polymer materials has the advantages of reducing costs and maintaining better transparency of the product. At present, research on composite modification of polymer materials with sodium sulfate is very rare, and sodium sulfate filling modification Polypropylene carbonate has not been reported in the literature.

Contents of the invention

The purpose of the present invention is to prepare polypropylene carbonate / sodium sulfate transparent fully degradable composite material through the method of filling and modifying sodium sulfate. Filling and modifying polypropylene carbonate with sodium sulfate can serve multiple purposes: it can not only improve the mechanical properties, glass transition temperature and heat resistance of the composite material, but also maintain its original transparency, and at the same time can greatly The cost of material products can be significantly reduced. In addition, when the composite material product is discarded, the water absorption of sodium bicarbonate in the composite material can accelerate the degradation of the polypropylene carbonate matrix.

Above-mentioned invention purpose is realized by following technical scheme:

A transparent and fully degradable composite material of polypropylene carbonate/sodium sodium sulfate, the components of which are by weight: polypropylene carbonate 60%-95%, sodium sulfate 5%-40%, surface modifier 0-1 %, lubricant 0-0.5%.

For the above-mentioned polypropylene carbonate/naphtalate transparent fully degradable composite material, a preferred solution is that the particle size of the naphtha powder is 800-3000 mesh (preferably 900-2500 mesh, more preferably 1800 mesh).

For the above-mentioned polypropylene carbonate/sodium sulfate transparent fully degradable composite material, a preferred solution is that the whiteness of the sodium sulfate is greater than 90.

The above-mentioned polypropylene carbonate/yuan Mingfen transparent fully degradable composite material, the preferred scheme is that the surface modifier is a silane coupling agent, a titanate coupling agent and an amphiphilic water-suppressing coupling agent. One or more than one.

The above-mentioned polypropylene carbonate/starch powder transparent fully degradable composite material, preferred scheme is, described lubricant is one or a kind of in paraffin, stearic acid, barium stearate, zinc stearate above.

The aforementioned polypropylene carbonate/yuanming powder transparent fully degradable composite material, preferred scheme is, described polypropylene carbonate is the complete alternating copolymer of carbon dioxide and propylene oxide, and the weight of carbon dioxide structure in its main chain structure The percentage is 43%, and the number average molecular weight is above 40,000.

The preparation method of described polypropylene carbonate/Nauramine transparent fully degradable composite material, the steps are as follows:

(1) Add the sodium bicarbonate into a high-speed mixer, stir and heat to 90-110°C, dry and exhaust, then pump in a non-aqueous surface modifier in the form of a fine mist under stirring, stir for 10-20 minutes, and leave spare material;

(2) Mix polypropylene carbonate pellets, surface-modified sodium sulfate and lubricant in a high-speed kneader, and then transfer the mixture to an internal mixer, single-screw extruder or twin-screw extruder Melting compounding is carried out in the machine, and the temperature of melting compounding is controlled at 150-180°C. The extruded material is air-cooled and pelletized to obtain a composite material.

In the above-mentioned preparation method, the preferred scheme is that the non-aqueous solution of the surface modifier in step (1) is an alcohol, ketone and hydrocarbon solution of the surface modifier.

In the above-mentioned preparation method, the preferred solution is that in step (1), adding Yuanming powder to a high-speed mixer, stirring and heating to 100°C.

The polypropylene carbonate/polysaccharide transparent fully degradable composite material of the present invention can be prepared by conventional melt blending methods such as banburying, single-screw extrusion, and twin-screw extrusion. The preparation process comprises the following steps: first add the Yuanming powder to a high-speed mixer and stir and heat to 100°C, dry and exhaust, then pump in a fine mist coupling agent non-aqueous solution (such as alcohol, ketone and hydrocarbon) under stirring. etc. as a solvent), the stirring process can be completed in 10-20 minutes, and the material is discharged for later use; then the polypropylene carbonate pellets, surface-modified sodium sulfate and lubricant are processed in a high-speed kneader according to the formula dosage Mix, and then transfer the mixture to an internal mixer, single-screw extruder or twin-screw extruder for melt compounding. The temperature of melt compounding is controlled at 150-180°C. The extruded material is air-cooled and pelletized to obtain Composite pellets.

The beneficial effects of the present invention are:

① The refractive index of sodium sulfate as a filler is very close to that of polypropylene carbonate, so it has little effect on the transparency of the product after being compounded with the resin matrix;

② Yuanming powder has sufficient sources, convenient processing, and low price, which can greatly reduce the cost of composite products;

③ The oil absorption of sodium sulfate is lower than that of traditional fillers such as calcium carbonate, which can reduce the amount of other additives used in the processing of composite materials and help reduce the manufacturing cost of products;

④ When the polypropylene carbonate / sodium sulfate composite product is discarded to nature, the sodium sulfate in the product can absorb moisture in the atmosphere and keep the product in a moist state, thereby accelerating its biodegradation rate;

5. The preparation equipment of composite material in the inventive method is the general equipment in industrial production;

⑥ The fully degradable plastic pellets prepared by the present invention can be directly injection molded or extruded without adding any other additives, and the production process is simple and efficient.

Detailed ways

The technical solutions of the present invention will be described in detail below in conjunction with the examples, but the scope of protection is not limited thereto. The raw materials used in the examples can all be purchased from the market. The polypropylene carbonate used in the following examples was purchased from Inner Mongolia Mengxi High-tech Materials Co., Ltd., the sodium sulfate was purchased from Jiangsu Nanfeng Yuanming Powder Co., Ltd., and γ-aminopropyl Triethoxysilane coupling agent (product brand CG-550) was purchased from Nanjing Chengong Organic Silicon Material Co., Ltd., and lubricant stearic acid (product brand 200) was purchased from Shandong Zibo Fengsen Oil Chemical Co., Ltd.

Example 1 A transparent and fully degradable composite material of polypropylene carbonate/sulfur sodium, the composition and properties of the composite material are shown in Table 1. First weigh a certain amount of sodium sulfate and silane coupling agent (preferably γ-aminopropyltriethoxysilane coupling agent, the amount is 1wt% of the filler), and prepare the coupling agent into an anhydrous ethanol solution, first Add a certain amount of Yuanming powder (the particle size of Yuanming powder is 800 mesh, and the whiteness is greater than 90) into the high-speed mixer, stir and heat to 100°C, dry and exhaust, and then pump into the coupling in a fine mist under stirring agent solution, continue to stir for 15 minutes, discharge the material, and dry it at 100°C for 3 hours for later use; then put the polypropylene carbonate pellets, surface-modified sodium sulfate and lubricant stearic acid in a high-speed kneader according to the formula The amount of mixing is carried out, and after discharge, a small single-screw extruder in the laboratory is used to melt and blend to prepare composite materials. The body transport area temperature is 120-140°C. The obtained composite material was pressed into sheets by a flat vulcanizing machine, and the mechanical property test was carried out according to the standard sample preparation of ISO 527-2-2012; the light transmittance test was carried out according to GB2410-2008, and the thickness of the sample was 0.2mm.

Embodiment 2-5 is a kind of transparent fully degradable composite material of polypropylene carbonate/naphtalate, at first weigh a certain amount of naphthalene and silane coupling agent (preferably gamma-aminopropyltriethoxysilane coupling agent , the dosage is 1wt% of the filler), the coupling agent is formulated into an anhydrous ethanol solution, and a certain amount of sodium sulfate (the particle size of the sodium carbonate is 3000 mesh, and the whiteness is greater than 90) is added to a high-speed mixer to stir and heat to 100°C, dry and exhaust, then pump in a fine mist coupling agent solution under stirring, continue to stir for 15 minutes before discharging, and dry at 100°C for 3 hours for later use; then the polypropylene carbonate pellets, surface After the modified sodium sulfate and lubricant (paraffin and barium stearate) are mixed in a high-speed kneader according to the formula dosage, then the mixture is transferred to an internal mixer for melting and compounding, the mixing speed is 50rpm, and the melting The composite temperature is controlled at 160°C. The obtained composite material was pressed into sheets by a flat vulcanizing machine, and the mechanical property test was carried out according to the standard sample preparation of ISO 527-2-2012; the light transmittance test was carried out according to GB2410-2008, and the thickness of the sample was 0.2mm. The composition and properties of the composite materials are shown in Table 1.

Example 6-7 A transparent and fully degradable composite material of poly(propylene carbonate)/sodium sodium sulfate, the dried sodium sulfate (the particle size of the sodium sulfate is 1800 mesh, and the whiteness is greater than 90), polypropylene carbonate particles Materials and lubricant zinc stearate are mixed in a high-speed kneader according to the formula dosage, then the mixture is transferred to an internal mixer for melt compounding, the mixing speed is 50rpm, and the temperature of melt compounding is controlled at 160°C. The obtained composite material was pressed into sheets by a flat vulcanizing machine, and the mechanical property test was carried out according to the standard sample preparation of ISO 527-2-2012; the light transmittance test was carried out according to GB2410-2008, and the thickness of the sample was 0.2mm. The composition and properties of the composite materials are shown in Table 1.

Table 1 Composition and properties of composite materials

It can be seen from the above table: the introduction of sodium sulfate can greatly improve the tensile strength of the composite material, the tensile strength of the composite material filled with 5wt% modified sodium sulfate is 48.9% higher than that of the base material, and the composite material filled with 30wt% modified sodium The tensile strength of the composite material of the powder is still 16.0% higher than that of the base material. At the same time, the light transmittance of the material is well maintained, and the composite material with the filling amount of sodium sulfate within 20% maintains more than 50% of the light transmittance of the matrix material.

The completion of the present invention benefits from the support of the Shandong Provincial Science and Technology Research Project "Preparation of High-Efficiency Nano-loaded Zinc Carboxylate Catalyst and Catalytic Carbon Dioxide Synthesis of Degradable Plastics" (Project No. 2009GG10003019).

Claims (8)

1. A transparent fully degradable composite material of polypropylene carbonate/sodium sodium sulfate, characterized in that the components are by weight: polypropylene carbonate 60%-95%, sodium sulfate 5%-40%, surface modified agent 0-1%, lubricant 0-0.5%; the surface modifier is one or more of silane coupling agent, titanate coupling agent and amphiphilic hydrostatic coupling agent; the The lubricant is one or more of paraffin, stearic acid, barium stearate, and zinc stearate; the polypropylene carbonate is a complete alternating copolymer of carbon dioxide and propylene oxide, and the structure of carbon dioxide is in its main The chain structure accounts for 43% by weight, and the number average molecular weight is above 40,000. 2. The transparent fully degradable composite material of poly(propylene carbonate)/naphtalate according to claim 1, characterized in that, the granularity of the polymethylene carbonate is 800-3000 mesh. 3. The transparent and fully degradable composite material of polypropylene carbonate/sodium sulfate according to claim 2, characterized in that, the particle size of the sodium sulfate is 900-2500 mesh. 4. The transparent and fully degradable composite material of polypropylene carbonate/sodium sulfate according to claim 2, characterized in that, the particle size of the sodium sulfate is 1800 mesh. 5. The transparent fully degradable composite material of polypropylene carbonate/sodium sulfate according to claim 1, characterized in that, the whiteness of the sodium sulfate is greater than 90. 6. according to the preparation method of the polypropylene carbonate/the transparent full degradable composite material of sodium sulfate described in any one of claim 1-5, it is characterized in that, the steps are as follows: (1) Add the sodium bicarbonate into a high-speed mixer, stir and heat to 90-110°C, dry and exhaust, then pump in a non-aqueous surface modifier in the form of a fine mist under stirring, stir for 10-20 minutes, and leave spare material; (2) Mix polypropylene carbonate pellets, surface-modified sodium sulfate and lubricant in a high-speed kneader, and then transfer the mixture to an internal mixer, single-screw extruder or twin-screw extruder Melting compounding is carried out in the machine, and the temperature of melting compounding is controlled at 150-180°C. The extruded material is air-cooled and pelletized to obtain a composite material. 7. The preparation method according to claim 6, characterized in that the non-aqueous solution of the surface modifier in step (1) is an alcohol, ketone and hydrocarbon solution of the surface modifier. 8. The preparation method according to claim 6, characterized in that, in step (1), adding Yuanming powder to a high-speed mixer, stirring and heating to 100°C.