JPH0459834A - Production of thermoplastic vegetable material and production of molded article using the same material - Google Patents

Abstract

PURPOSE:To obtain the title material capable of freely molding and carrying out recycle of the molded article and burr, etc., by blending a vegetable fiber, etc., with a specific prepolymer and stabilizer at a specific ratio and then curing the blend by using water. CONSTITUTION:(A) 100 pts.wt. vegetable fiber or powder grain of wood waste, soybean refuse, rice hull, etc., is blended with (B) 1-100 pts.wt. terminal NCO- containing prepolymer obtained by reacting a polyoxyalkylene polyol with an organic polyisocyanate at an equivalent ratio of NCO/OH of 1.5-20 and (C) 0.001-2.00 pts.wt. stabilizer such as 2-mercaptobenzoimidazole, a coloring agent and a plasticizer, etc., as necessary added and the blend is cured by using water or moisture to provide the objective material. The material is subjected to heat molding at 80-200 deg.C to provide the molded article.

Description

[Detailed description of the invention] [Purpose of the invention]

[Industrial Application Field] The present invention relates to a thermoplastic vegetable material and a method for producing a molded article using the same. [Prior Art] (1) Background Conventionally, a method for forming powder or granular solids such as wood chips into a plate shape or the like is disclosed in Japanese Patent Application Laid-Open No. 511-108932.
As seen in JP-A No. 58-83435, a prepolymer or organic polyincyanate having an incyanate group at the molecular end is attached to the powder or granular solid, and then spread on a substrate. There was a way to apply pressure. (2) Problems with the conventional technology However, the above method takes advantage of the fact that the prepolymer or organic polyisocyanate having terminal incyanate groups is a thermosetting resin, and uses the prepolymer or organic polyisocyanate as an adhesive. Therefore, the obtained product was a hard thermosetting product, and it was impossible to extrude or heat compression mold it. In addition, since there is no thermoplasticity, paris (f) generated during molding
There was no other way to dispose of defective products that did not meet standard dimensions, such as lashins or other defective products that did not meet standard dimensions, other than to throw them away or incinerate them. [Problems to be Solved by the Invention] The purpose of the present invention is to solve the above-mentioned drawbacks of molded products, including conventional thermosetting wood molded products, by imparting thermoplasticity to vegetable materials. .

[Structure of invention I! t, ]

[Means for Solving the Problems] (1) Overview In order to achieve the above objects, the present invention provides (A) 100 parts by weight of vegetable fiber or powder, (B) polyoxyalkylene polyol and organic polyin Cyanate and NCO/
1 to 100 parts by weight of a terminal NCD group-containing prepolymer reacted at an OH equivalent ratio of 1.5 to 20, and (C) 0.0 parts by weight of a stabilizer.
01 to 2.00 parts by weight, and (D) curing with water or moisture;
The gist of the present invention is a method for producing a molded article, which is characterized by heat molding in a temperature range of 0°C. Below, various matters related to the structure of the invention will be explained separately. (2) Vegetable fiber or powder (component (^)) The vegetable fiber or powder (component (A)) in the present invention includes wood chips,
Examples include wood flour, fiber waste, buckwheat husks, rice straw, rice bran, bean meal, rice husks, wheat husks, wood wool, and cork powder. (3) Prepolymer (component (B)) Prepolymer (component (B)) used in carrying out the method of the present invention
) The polyoxyalkylene polyol that is the -component of
Ethylene glycol, diethylene glycol, propylene glycol, hydroquinone, bisphenol A, 1
．． Low molecular weight polyols such as 6-hexanediol, neopentyl glycol, glycerin, trimethylolpropane, 1,2,6-hexanediol, pentaerythritol, α-methyl glycoside, sorbitol, sucrose, castor oil, or ethylenediamine, diethylenetriamine Addition polymerization of ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetrahydrofuran, etc. alone or in combination with low molecular weight mono- or polyamines such as , piperazine, methylamine, n-butylamine, aniline, xylene diamine, etc. It is something. Note that when mixed alkylene oxide is subjected to addition polymerization, the addition polymerization form is random. Any block is fine. In addition, in addition to the polyoxyalkylene polyol, low-molecular polyols such as ethylene glycol, propylene glycol, butanediol, etc. may be used in combination. Next, organic polyisocyanate refers to tolylene diisocyanate (DI), crude tolylene diisocyanate)
(crude 1↑DI), diphenylmethane diincyanate C
MDI), polymethylene polyphenylisocyanate, hexamethylene diisocyanate, xylene diisocyanate, naphthalene diisocyanate, inphorone diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate,
4,4-methylene-bis-(cyclohexane isocyanate) alone or as a mixture. These polyisocyanates may be so-called modified polyincyanates that have been modified with various modifiers or treatments. The prepolymer in the present invention is a urethane prepolymer composition obtained by reacting the polyoxyalkylene polyol with the organic polyisocyanate and containing substantially unreacted organic polyisocyanate groups. In the reaction between the polyoxyalkylene polyol and the organic polyinsyanate, the N0D10H equivalent ratio is 1.5 to 20. Preferably it is 1.8-10. If the NCO/OH equivalent ratio is less than 1.5, the viscosity of the prepolymer will increase and workability will deteriorate;
If it exceeds 0, recycling becomes impossible and reunicyclicity is lost. (0 Stabilizer (Component (C)) The stabilizer (Component (C)) in the present invention includes 2-mercaptobenzimidazole, N,N'-diphenylphenylenediamine, 2,6-sibutylhydroxytoluene, 2, 5-di-ethylhydroquinone, butylhydroxyanisole, 2.5-di-t-butylhydroquinone, dialkylphenylenediamine, tophenyl-N
-isopropylphenylenediamine, 2,2-methylenebis(4-methyl-5-t-butylphenol),
2.2-methylenebis(4-ethyl-6-t-butylphenol), 4.4-thiobis(et-t-butyl-
■-cresol), 1,3.5-tris (4°-t
-Butyl-3°-hydroxy-2゛,6°-dimethylbenzyl)in cyanurate, 2-tert-butyl-8-(3
'-t-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenylacrylate, N,N'-
Bis-[3-(3°,5°-di-t-butyl-4°-hydroxyphenyl)propionyl] hydrazine, hydroquinone monomethyl ether, hydroquinone, phenothiazine, pyrogallol, pt-butylcatechol, 1-nitroso-2 - Naphthol, benzoquinone, pyrocatechol, cuperone, tetraethylthiuram disulfide, bis(2,2,8,8-tetramethyl-4-
pipeziridinyl) sepacate, tetrachlorobenzoquinone, tetrabromohydroquinone, 1,1. L-tetramethyl-4,4(methylene-di-p-phenylene) disemicarbazide, tomethyl-P-7 minophenol, hydrazine conductor, N,N'-hexamethylene bis(3,5
-di-t-butyl-4-hydroxyhydrocinnamide)
, 2.2'-thiobis(4-methyl-6-butylphenol), 4,4°-thiobis(3-methyl-6-t-butylphenol), 2.2-thiodiethylenebis-[3-(3 °, 5-di-t-butyl-4'-hydroxyphenyl)propionate], bis[2-
t-Butyl-4-methyl-8-(3°-t-butyl-5
°-Methyl-2'-hydroxybenzyl)phenyl]terephthalate, 1,1.3-)lis(2°-methyl-4
°-hydroxy-5'-t-butylphenyl)butane,
1,3,5-trimethyl-2,4,8-tris (3″,
5'-di-t-butyl-4°-hydroxybenzyl)benzene, tris(3,5-di-t-butyl-4-hydroxybenzyl)in cyanurate, 1,3.5-)lis[3-( 3°,5°-di-t-butyl-4°-hydroxyphenyl)propionyloxy]ethyl isocyanurate, 1,3.5-tris(4-t-butyl-3′-hydroxy-2°el-dimethylbenzyl) incyanurate, tetrakis[methylene-3-(3°,5°-di-t-butyl-4′-hydroxyphenyl)propionate comethane, calcium (3,5-di-t-butyl-
4-Hydroxybenzylmonoethylphosphoone))
, 2. Examples include hindered phenolic antioxidants such as i, e-tri-t-butylphenol. (5) Other compounding agents In the production method of the present invention, in addition to the above basic ingredients, colorants, plasticizers, lubricants, surfactants, solvents, antifoaming agents,
Auxiliary agents such as inorganic fillers, light stabilizers, ultraviolet absorbers, and flame retardants may be used in combination. (6) Usage amount of each component The usage amount of the prepolymer is 1 to 100 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the powder of vegetable fiber If the amount exceeds 100 parts by weight, the properties of the resin will become strong and the good properties of the plant material will be lost. The amount of stabilizer used is 0.001 to 2.00 parts by weight, preferably 1.00 parts by weight of 0.01N, and 0.001 to 2.00 parts by weight.
If it is less than 1 part by weight, the thermal stability of the material of the present invention is poor;
If the amount is more than 0 parts by weight, the cost of the material of the present invention becomes high and the physical properties of the molded product deteriorate. The amount of water or moisture to be used is equal to or more than the amount of unreacted incyanate groups in the prepolymer, and may be moisture in the air or moisture in vegetable fibers or powder particles. The reactive incyanate may be crosslinked. (7) Compounding method Regarding the usage of prepolymer and water, either the prepolymer and water are mixed in advance and then the vegetable fibers or powder particles are added, or the prepolymer and water are simultaneously sprayed onto the vegetable fibers or powder particles. Alternatively, the vegetable fibers or powder particles may be wetted with water and then mixed with the prepolymer, or the vegetable fibers or powder particles may be mixed with the prepolymer and left in the air. The stabilizer may be blended in advance into the prepolymer, or may be mixed simultaneously with the prepolymer, vegetable fiber or powder, and water. (8) Molding If the obtained resin-treated vegetable material has a high moisture content, it is dried and then thermoformed. To make it easier to put the material into the mold, it may be pulverized before thermoforming. After the thermoforming is heated and softened, the material is placed on either the male or female mold and placed under vacuum or pressure. Shape with. The heating temperature is 80~
The temperature is 200°C, preferably 100-170°C. 200
Temperatures above ℃ cause the vegetable material to burn. Furthermore, if a stabilizer is not used in combination, decomposition is likely to occur, making thermoforming impossible. [Function] The present invention is a method for producing a plant-based material using waste materials such as wood flour, wood fibers, and rice husks as the main components, and the molded article obtained from the material is a method for producing a plant-based material, in particular a wood-based material. It retains the heat retention, insulation, moisture control, and shock absorption properties of the material. In addition, since the prepolymer is loosely crosslinked by moisture, the molded product becomes a type of thermoplastic resin and covers the surface of the wood material, making it possible to perform thermal compression processing. In addition, the carbon dioxide gas generated when the prepolymer is crosslinked with water is dispersed in the resin to form a foam, making the resulting thermoplastic resin more flexible and therefore easier to process through hot compression. becomes. Furthermore, in the method for producing a vegetable material of the present invention, since a relatively low molecular weight prepolymer is used as a raw material, it has a low viscosity even at low temperatures and can be easily mixed with vegetable fibers or powder particles. Furthermore, since the vegetable material produced by the production method of the present invention is made from polyether polyol rather than polyester polyol, it has good hydrolytic stability, and also has good thermal stability when used in combination with a specific stabilizer. The molded body is
It can be recycled as a thermoplastic resin. [Examples] Below: Examples and effects of embodying the invention will be described through Examples and Comparative Examples, but the examples are merely for explanation and are not intended to limit the idea of the invention. Example 1 At room temperature, wood flour (ground flour discharged from a factory that saws logs of cedar and cypress, with a moisture content of 20% and a particle size of 50 to 100 mm) was prepared.
) 100 parts, terminal NCO obtained by reacting 68.4 parts of random diol with a molecular weight of 3000 obtained by adding a mixture of propylene oxide and ethylene oxide 50150 (weight ratio) to diethylene glycol and 10.6 parts of tolylene diisocyanate. Group content 2.7% (N
eo10H equivalent ratio 2.00) prepolymer 30 parts, stabilizer (hydroquinone monomethyl ether) 0.05
The mixture was kneaded in a kneader until the generation of carbon dioxide gas ceased. The obtained mixed wire material was taken out and dried at 80° C. to obtain a granular wood powder having a bulk specific gravity of 0.20. The obtained powder was press-molded at 140°C for 10 minutes under the pressure of 15 kg 7'cm intestine 2 to have a density of 0.40.
g/CM3, bending strength 23kg/cm2 (JIS
A 5808) (7) A lightweight podo was obtained. The obtained lightweight board is re-pulverized into chips of 2 to 3 cm, and press-molded again at 140°C for 15 kg/c for 2.10 minutes to produce a board with a density of 0.421/cs3 and a bending strength of 22 kg/cm2. I was able to play it. Trap cliff seal at room temperature, bulk specific gravity 0.064 g/cm3 Corri powder 10
0 parts, 75.5 parts of polyoxypropylene glycol with a molecular weight of 4000, 8.4 parts of block triol (molecular weight 7000), which is obtained by adding propylene oxide and ethylene oxide to glycerin at a ratio of 70730 (weight ratio), and diphenylmethane diisocyanate) 1B, Prepolymer with 3.8% terminal NGO obtained by reaction with 2 parts (NC
After kneading 50 parts (O/OH equivalent ratio 3.00) and 0.10 parts of a stabilizer (phenothiazine) in a kneader, 15 parts of water was further added and kneaded. When the selected mixed wire is taken out and dried at 80°C, the bulk specific gravity becomes 0. (A powder of 1'90g1cm3 was obtained.The obtained powder was press-molded for 159 minutes at 100°C under a pressure of 10kg/cm2 to have a density of 0.28g.
A cork board with /cs2 of 3, bending strength of 15'kg, and /cs2 was obtained. [Fruit] 11 units Rice husk powder (particle size 50-100 mm) at room temperature 100
A prepolymer with a terminal NCO group content of 7.0% (NC:
010H equivalent ratio 3.1) 20 parts and stabilizer (2,6
-Sibutylhydroxytoluene) 0.10 parts and 5 parts of water were added and kneaded in a Ni-Goo, and the selected mixture was dried to obtain pellets having a bulk specific gravity of 0.35 g/c3. 20 kg of the obtained pellets were heated at 170°C for 15 minutes.
By heat pressing under the conditions of /cs2, the specific gravity is 0.
A molded plate with a bending strength of 98 and a bending strength of 320 kg/cm2 was obtained. Comparative Example 1 Instead of the prepolymer of Example 1, a prepolymer with a terminal NCO group content of 15% was obtained by reacting a triol with a molecular weight of 3000 obtained by adding propylene oxide to glycerin and polymethylene polyphenylisocyanate. (Neo10H equivalent ratio 4.130) was used to obtain a powder (bulk specific gravity 0.22) in the same manner as on the same side. The obtained powder was press-molded for 10 minutes at 140° C. and 15 kg/c fat 2, but it could not be molded and did not exhibit thermoplasticity or recyclability. The pellets were obtained in the same manner as in Example 3 except that the stabilizer was not used in combination.
The molded plate heat-pressed under C112 conditions has a specific gravity of 0.98.
When the bending strength was 7 kg/cm2, the pellets were peeled off from the molded plate. Since the surface was sticky, it was assumed that this was caused by thermal decomposition of the material.

【Effect of the invention】

As explained above, the present invention provides a thermoplastic vegetable material by blending a specific prepolymer and stabilizer with a vegetable raw material in a specific ratio. This plant-based material has excellent hydrolysis resistance and thermal stability, so it can be freely heated and molded, and the selected molded material can be crushed after use and used as a raw material for re-molding. It is useful for resource saving and environmental conservation through recycling. Similarly, ash in the molding process
g) Since other waste can be reused, resources can be used effectively and there is no risk of air pollution caused by incineration. Patent applicant Daiichi Kogyo Seiyaku Co., Ltd.

Claims (1)

[Scope of Claims] 1 (A) 100 parts by weight of vegetable fiber or powder, and (B)
1 to 100 parts by weight of a prepolymer containing a terminal NCO group, which is obtained by reacting a polyoxyalkylene polyol and an organic polyisocyanate at an NCO/OH equivalent ratio of 1.5 to 20;
C) A method for producing a thermoplastic vegetable material, which comprises mixing with 0.001 to 2.00 parts by weight of a stabilizer, and then curing the mixture with (D) water or moisture. 2. The thermoplastic vegetable material according to claim 1 at 80 to 20
1. A method for producing a molded article, comprising heating and molding in a temperature range of 0°C.