CN1228388C - Composite material and itd preparation method - Google Patents

Abstract

The invention discloses a composite material obtained by using soybean dregs, soybean powder and other soybean by-products, polyether polyol or polyester polyol and diisocyanate as raw materials and a preparation method thereof. First, the polyurethane prepolymer is obtained by reacting polyether polyol or polyester polyol with diisocyanate, and then the polyurethane prepolymer is mixed with soybean dregs or soybean flour in a certain proportion, and the polyurethane prepolymer is mixed under the condition of no solvent and no external plasticizer. After the reaction, the sheet or other shape materials are obtained by hot pressing. It is also possible to mix polyether polyol or polyester polyol, diisocyanate with soybean dregs or soybean flour in a certain proportion, and directly extrude and react through a screw machine, and obtain a composite material after hot pressing. By changing the types of soybean by-products, polyether polyols or polyester polyols, diisocyanates and their ratios, materials with various properties from plastics to elastomers can be obtained. Therefore, the soybean dregs or soybean flour composite material is a novel material with simple process and low cost.

Description

A kind of composite material and preparation method thereof

technical field

The invention relates to a composite material obtained from soybean dregs, soybean flour and other soybean by-products, polyether polyol or polyester polyol, and diisocyanate as raw materials and a preparation method thereof, which belongs to the field of polymer chemistry and also belongs to the science of polymer materials field.

Background technique

With the depletion of petroleum resources and the pollution of non-degradable synthetic polymers to the environment, the research and development of "green polymers" has become the frontier of polymer science. my country is rich in soybeans, so it has abundant resources of soybean products. However, my country's soybean oil content (17%) is significantly lower than that of the United States (23%), while the price is 40% higher than that of the international market. One of the countermeasures is to increase the utilization rate of by-products after oil extraction and extraction of soybean protein. Transform it into industrial materials, thereby increasing the value of agricultural by-products. Usually, after soybean oil is extracted, a large amount of defatted soybean flour, soybean protein isolate, and soybean residue can be obtained. They have both commercial value and biodegradability, so they are a sustainable development strategy. It is an environmentally friendly natural polymer material that needs to be researched and developed vigorously. For example, soybean protein plastics were reported in the 1930s and 1940s (Ind. Eng. Chem., 32, 1002, 1940). But at that time, it was a period of rapid development of petroleum products, and the processing and development of soybean by-products did not attract enough attention. In recent years, research on soybean protein has attracted international attention, and it has become an important raw material for emerging "industrial protein plastics". Foreign countries mainly focus on soybean products as adhesives (J.Am.Oil Chem.Soc., 72 (12), 1461, 1995), plastics (J.Polymer, 42, 2569, 2001), textile fibers (J. .Appl.Polym.Sci., 71, 11, 1999) and various packaging materials (Polym.Prepr., 39(2), 148, 1998) and other fields, while domestic soybean by-products in plastics, packaging materials The application research of respect such as is still lacking (Ind.Eng.Chem.Res., 40,1879,2001).

Polyurethane is a polymer material with excellent performance and wide application. Adding soybean powder, soybean protein, etc. to the polyurethane system to prepare polyurethane foam has attracted the attention of foreign scholars (J.Appl.Polym.Sci., 81, 2027, 2001; J.Appl.Polym.Sci., 80, 10, 2001) . Soybean flour is the material after soybean oil extraction, and soybean dregs are the residues of soybean protein isolate after soybean flour is extracted by alkali dissolution method. They are used as raw materials to react with polyether polyol or polyester polyol and diisocyanate through chemical reaction and heat treatment. There is no report on the preparation of composite materials by pressing.

Contents of the invention

The problem to be solved by the present invention is to provide a composite material and a preparation method thereof. The composite material uses soybean by-products such as soybean dregs and soybean flour, polyether polyol or polyester polyol, and diisocyanate as main raw materials, and is prepared in a solvent-free and It is prepared under the condition of no external plasticizer, and the production process is simple and the cost is low.

The technical solution provided by the present invention is: a composite material, which is obtained by extruding reaction of a screw machine and hot pressing with soybean dregs or soybean flour, polyether polyol or polyester polyol and diisocyanate as raw materials; wherein the polyether polyol The molar ratio of alcohol or polyester polyol to diisocyanate is 1:1.5 to 1:2, and the mass ratio of the sum of the mass of polyether polyol or polyester polyol and diisocyanate to soybean dregs or soybean flour is 3:7 to 5 : 5.

The composite material of the present invention can be obtained by mixing polyether polyol or polyester polyol and diisocyanate in a molar ratio of 1:1.5 to 1:2, and reacting at 70 to 90°C to obtain a polyurethane pre-polyurethane terminated in whole or in part with isocyanate groups. The polymer is obtained by mixing the polyurethane prepolymer with soybean dregs or soybean flour at a mass ratio of 3:7 to 5:5, extruding and reacting through a screw machine, and then forming by hot pressing.

Or it can be obtained by directly mixing polyether polyol or polyester polyol with diisocyanate, soybean dregs or soybean powder at 70-90°C, extruding and reacting through a screw machine, and forming by hot pressing.

The present invention also provides a preparation method of the above-mentioned composite material: mixing polyether polyol or polyester polyol and diisocyanate at a molar ratio of 1:1.5 to 1:2, and reacting at a constant temperature of 70-90°C for 2-3 hours , to obtain all or part of the isocyanate-terminated polyurethane prepolymer; the polyurethane prepolymer and soybean dregs or soybean flour are mixed evenly in a mass ratio of 3:7 to 5:5, and the reaction is extruded by a screw machine, and then Put it into a mold and heat-press at 110-140°C to obtain the required composite material.

The more convenient preparation method of the above-mentioned composite material is: at 70-90°C, mix polyether polyol or polyester polyol with diisocyanate, soybean dregs or soybean flour at the same time, and extrude the reaction through a screw machine, and heat-press molding Obtain; Wherein the mol ratio of polyether polyol or polyester polyol and diisocyanate is 1: 1.5 to 1: 2, the quality of polyether polyol or polyester polyol and diisocyanate and the mass ratio with soybean dregs or soybean flour are 3:7 to 5:5.

The present invention can obtain polyurethane with different mechanical properties, water resistance and biodegradability by selecting different soybean by-products, different polyether polyols or polyester polyols, adjusting the ratio of various substances, changing reaction and hot pressing conditions Materials, with their high technological content, are innovative. The invention has simple production process and low cost, and the obtained composite material can be prepared into the shapes of various hot-pressing molds as required, and is practical in tourism products, daily necessities, gardening and craft industries.

The technical progress of the present invention lies in: (1) make full use of abundant source, cheap soybean powder and soybean dregs as main raw materials; (2) greatly improve the The machinability of soybean dregs and soybean flour; (3) materials with good mechanical properties and water resistance can be obtained.

Detailed ways

The technical scheme of the present invention will be further described below in conjunction with specific embodiments:

Example 1

Mix dry polypropylene glycol and freshly steamed 2,4-toluene diisocyanate in a three-necked flask at a molar ratio of 1:2, heat to 85°C with stirring, then keep warm and steam for 2.5 hours to obtain isocyanate-terminated polyurethane prepolymer. The polyurethane prepolymer is mixed with the dried soybean dregs at a mass ratio of 4:6, and is extruded by a screw machine for reaction. The extrusion conditions are: the temperatures from the injection to the outlet are respectively 90, 100 and 110°C. The extruded material was hot-pressed at 20 MPa and 120° C. for 7 minutes on a hot press, and cooled to below 50° C. to take out the hot-pressed sheet. The mechanical properties and water resistance of the material are shown in the attached table.

Example 2

The whole preparation process is the same as in Example 1, except that the mass ratio of polyurethane prepolymer to soybean dregs is changed to 5:5.

Example 3

The whole preparation process is the same as in Example 1, except that the soybean dregs are replaced by soybean flour, and the extrusion conditions are replaced by: the temperatures from the injection to the outlet are respectively 80, 90 and 100° C., and the hot pressing temperature is 110° C.

Example 4

The whole preparation process is the same as that of Example 3, except that the mass ratio of polyurethane prepolymer to soybean flour is changed to 5:5.

Example 5

Mix dry polycaprolactone with a molecular weight of 400, freshly steamed 2,4-toluene diisocyanate and dried soybean dregs evenly, wherein the molar ratio of polycaprolactone to 2,4-toluene diisocyanate is 1:1.5 , The mass ratio of the sum of polycaprolactone and 2,4-toluene diisocyanate to soybean dregs is 4:6, and the mixture is extruded by a screw machine for reaction. The extrusion conditions are as follows: the temperature from the injection to the outlet is 110, 120 and 130°C respectively. The extruded material was hot-pressed at 20 MPa and 130°C for 10 minutes on a hot press, and cooled to below 50°C to take out the hot-pressed sheet.

Example 6

The entire preparation process is the same as in Example 5, except that the mass ratio of the sum of the polycaprolactone and 2,4-toluene diisocyanate to the soybean dregs is changed to 5:5.

Example 7

The whole preparation process is the same as in Example 6, except that the molar ratio of polycaprolactone and 2,4-toluene diisocyanate is changed to 1:1.7.

Example 8

Mix dry castor oil, freshly steamed 2,4-toluene diisocyanate and dried soybean dregs evenly, wherein the molar ratio of castor oil to 2,4-toluene diisocyanate is 1:1, castor oil to 2,4- The mass ratio of the sum of the mass of toluene diisocyanate to the soybean dregs is 4:6, and the mixture is extruded and reacted by a screw machine. The extrusion conditions are as follows: the temperature from the injection to the outlet is 110, 120 and 130°C respectively. The extruded material is hot-pressed at 20MPa and 140°C for 10 minutes on a hot press, and cooled to below 50°C to take out the hot-pressed sheet.

Mechanical properties and water resistance of hot-pressed composite sheets Tensile strength (MPa) Elongation at break (%) water resistance Water Absorption (%)* Example 1 Example 2 6.416.89 45.5100.4 0.470.55 66.752.0 Example 3 5.16 77.98 0.42 136.66 Example 4 5.01 131.63 0.48 126.19 Example 5 10.41 19.28 0.45 67.98 Example 6 11.73 43.61 0.46 39.88 Example 7 14.58 31.49 0.48 34.56 Example 8 25.5 16.6 0.61 20.43

*Water absorption: It is the weight gain rate of the sample soaked in distilled water at 25°C for 26 hours.

The above-mentioned polypropylene polyol is replaced by other polyether polyols or polyester polyols, and 2,4-toluene diisocyanate is replaced by other diisocyanates to obtain similar results.

Claims (5)

1. a matrix material is a raw material with soybean residue or the pure and mild vulcabond of soyflour, polyether glycol or polyester polyols, through screw rod machine extrusion reaction, hot-forming obtaining; Wherein the mol ratio of polyether glycol or the pure and mild vulcabond of polyester polyols is 1: 1.5 to 1: 2, and the quality sum of polyether glycol or the pure and mild vulcabond of polyester polyols and the mass ratio of soybean residue or soyflour are 3: 7 to 5: 5.

2. matrix material according to claim 1, it is characterized in that: by polyether glycol or polyester polyol and vulcabond mixed in molar ratio by 1: 1.5 to 1: 2, make the end capped polyurethane prepolymer of isocyano 70～90 ℃ of reactions, mix by the end capped polyurethane prepolymer of isocyano and soybean residue or soyflour mass ratio then by 3: 7 to 5: 5, and through screw rod machine extrusion reaction, hot-forming obtaining.

3. matrix material according to claim 2 is characterized in that: polyurethane prepolymer is all or part of with the end capped prepolymer of isocyano.

4. the preparation method of the described matrix material of claim 1, it is characterized in that: with polyether glycol or polyester polyol and vulcabond mixed in molar ratio by 1: 1.5 to 1: 2, reacted 2～3 hours down at 70～90 ℃, obtain all or part of with the end capped polyurethane prepolymer of isocyano; This polyurethane prepolymer and soybean residue or the soyflour mass ratio by 3: 7 to 5: 5 is mixed, through screw rod machine extrusion reaction, reinstall in the mould 110～140 ℃ hot-forming down, obtain required matrix material.

5. the preparation method of the described matrix material of claim 1 is characterized in that: under 70～90 ℃, simultaneously polyether glycol or polyester polyol mixed with vulcabond, soybean residue or soyflour, and through screw rod machine extrusion reaction, hot-forming obtaining; Wherein the mol ratio of polyether glycol or the pure and mild vulcabond of polyester polyols is 1: 1.5 to 1: 2, and the quality sum of polyether glycol or the pure and mild vulcabond of polyester polyols and the mass ratio of soybean residue or soyflour are 3: 7 to 5: 5.