JPH06166736A - Production of composite material of vinyl polymer and polyurethane - Google Patents

Abstract

PURPOSE:To obtain the subject composite material having small compression set and tension set and excellent thermal stability, productivity and processability and useful for molded article, etc., by carrying out a urethanization reaction and the radical polymerization of a vinyl monomer in an aqueous medium having a pH not higher than a specific level in the presence of an epoxy compound. CONSTITUTION:The objective composite material is produced by carrying out the urethanization reaction of an isocyanate compound (e.g. tolylene diisocyanate) with a polyol (e.g. hexanediol) and the radical polymerization reaction of a vinyl monomer such as vinyl chloride in the presence of an epoxy compound (e.g. epoxidized soybean oil) in an aqueous medium of pH 4 or below.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite of a vinyl polymer and polyurethane. In recent years, two or more kinds of polymers have been compounded,
It has been practically used in many cases as a polymer composition utilizing the advantages of each polymer. Vinyl polymers are widely used in all fields as general-purpose resins, while polyurethane is
It is a general-purpose resin with excellent wear resistance, low-temperature durability, and oil resistance, and it is also used for compounding with other resins. It is difficult to form a composite, and therefore there are various proposals for the composite technology. When the vinyl polymer is a vinyl chloride polymer, a diisocyanate compound and polyoxytetramethylene glycol are reacted in a vinyl chloride monomer to produce polyurethane, which is polymerized to graft polymer. This method is disclosed in JP-B-53-21038. A method of dissolving thermoplastic polyurethane in a vinyl chloride monomer and polymerizing it to form a composite is disclosed in Japanese Patent Laid-Open No.
58-37019, JP-A-58-40312, JP-A-58-426
No. 11 publication. [0006] Most of the conventional techniques are
In any case, there is concern about decomposition and deterioration due to contact of the isocyanate compound with water, either polyurethane that has been separately generated in advance is used, or polyurethane is generated in a vinyl chloride monomer, and in any case vinyl chloride Polyurethane is dissolved in the polymer and polymerized in an aqueous medium to obtain a composite. However, when a large amount of polyurethane is dissolved in the vinyl chloride monomer, the viscosity becomes high, and suspension or emulsification cannot be performed homogeneously in an aqueous medium, resulting in a distorted shape or huge particles. The content of the polymer on the wall is large and the productivity is reduced, so that the content of polyurethane is limited. Moreover, if the polyurethane contains a crosslinked structure and is insoluble in the vinyl chloride monomer, it cannot be formed into a composite.
Therefore, a vinyl polymer and various polyurethanes can be homogeneously compounded in an arbitrary ratio, and the productivity is good, and the shape of the resulting composite is uniform and the thermal stability of the composite is good. Provide a way to get. The present invention relates to a vinyl system which is subjected to a urethanization reaction between an isocyanate compound and a polyol and a radical polymerization reaction of a vinyl monomer in the presence of an epoxy compound in an aqueous medium having a pH of 4 or less. It is a method for producing a polymer-polyurethane composite. The vinyl-based monomer constituting the vinyl-based polymers of the present invention is a compound having an unsaturated double bond, such as vinyl chloride; vinylidene chloride; styrene, α.
-Aromatic vinyl represented by methylstyrene; (meth)
Acrylonitrile; (meth) acrylic acid esters; and the like. You may use these individually or 2 or more types which can be copolymerized. Furthermore, two unsaturated double bonds are contained in one molecule.
Well-known polyfunctional compounds having three or more, for example, divinylbenzene; ethylene glycol di (meth) acrylate,
(Meth) acrylic acid esters of polyhydric alcohols such as polyethylene glycol di (meth) acrylate; allyl compounds such as allyl (meth) acrylate, diallyl phthalate, diallyl maleate, triallyl cyanurate; diol divinyl ethers; butadiene, isoprene Such as dienes and their oligomers,
A small amount may be mixed with the vinyl-based monomer. As an example of the vinyl polymer of the present invention, there is polymerized vinyl chloride alone or a mixture of vinyl chloride and a compound having an unsaturated double bond copolymerizable with vinyl chloride. In the present invention, various well-known compounds can be used as the isocyanate compound as one of the components constituting the polyurethane. For example, aromatic diisocyanates such as tolylene diisocyanate, phenylene diisocyanate, chlorophenylene diisocyanate, naphthalene diisocyanate, tolidine diisocyanate; hexamethylene diisocyanate, lysine diisocyanate, methylene bis (cyclohexyl isocyanate), isophorone diisocyanate, trimethylhexamethylene diisocyanate, xylylene diisocyanate, etc. Of aliphatic and alicyclic diisocyanates; triisocyanates such as undecane triisocyanate, lysine ester triisocyanate and isocyanate methyl octamethyl diisocyanate; or polyfunctional isocyanates such as polyphenylmethane polyisocyanate and dimer of these isocyanate compounds Body Properly the trimeric acids and of the kind, there is an isocyanate compound having a terminal isocyanate group obtained by the reaction of active hydrogen compounds such as polyols or water and amino compounds of long-chain and the isocyanate compound.
Of these, aliphatic / alicyclic di- and triisocyanates are preferable. As the isocyanate compound, an active methylene compound. Also included are blocked isocyanate compounds that block-stabilize the above isocyanate compounds with a blocking agent such as oximes, lactams, phenols, alkylphenols, and basic nitrogen-containing compounds, and regenerate the isocyanate groups by heating. Further, as the isocyanate compound, it is possible to use the above-mentioned isocyanate compound as a mixture of several kinds. Among these isocyanate compounds, when a polyfunctional isocyanate having three or more isocyanate groups in one molecule is used, the resulting polyurethane has a crosslinked structure. Therefore, the amount of the polyfunctional isocyanate used may be selected according to the processability, mechanical properties, surface condition, etc. required for the composite. As the polyol which is the other component of the polyurethane, various known ones can be used. As relatively low molecular weight polyols, aliphatic, alicyclic, aromatic, and heterocyclic dihydroxy compounds, trihydroxy compounds, tetrahydroxy compounds, etc., such as hexanediol, decamethylenediol,
2,5-dimethyl-2,5-hexanediol, neopentyl glycol, diethylene glycol, cyclohexanedimethanol, bis (β-hydroxyethoxy) benzene,
p-xylene diol, dihydroxyethyl tetrahydrophthalate, trimethylolpropane, glycerin, 2-methylpropane-1,2,3-triol, 1,2,6-hexanetriol, pentaerythritol and aminopolyalcohols . As the polyol having a relatively high molecular weight, polyester polyol, polyether polyol, polycarbonate polyol, vinyl type polyol, diene type polyol, castor oil type polyol, silicone polyol, polyolefin type polyol and copolymers thereof are used. . Examples of polyester polyols include succinic acid, glutaric acid, adipic acid, azelaic acid,
Obtained by reacting a dicarboxylic acid selected from sebacic acid, dodecanoic acid, phthalic anhydride, isophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, maleic anhydride, fumaric acid, itaconic acid, etc. with a low molecular weight polyol. There is something. As another method, lactone compounds such as β-propiocratone, pivalolactone, δ-valerolactone, methyl-δ-valerolactone, ε-caprolactone, methyl-ε-caprolactone, dimethyl-ε-caprolactone and trimethyl-ε-caprolactone. There is also one obtained by reacting with a low molecular weight polyol. Examples of the polyether polyol include polytetramethylene glycol, polyethylene glycol, polypropylene glycol, polyoxypropylene glycol and the like. As the polycarbonate polyol, those obtained by the transesterification method from low molecular weight polyols and diallyl carbonate, dialkyl carbonate or ethylene carbonate, for example, poly-1,6-
Hexamethylene carbonate, poly-2,2'-bis (4-hydroxyhexyl) propane carbonate and the like are available. In addition to this, there is a so-called phosgene method or solvent method. In addition, vinyl-based polyols such as acrylic polyol obtained by copolymerization of acrylic acid ester with an acrylic monomer having a hydroxyl group such as β-hydroxyethyl acrylate and β-hydroxyl ethyl methacrylate, poly (1, 4-butadiene), poly (1,2-butadiene) and other polybutadiene polyols, polypropylene glycol ricinoleate and other castor oil-based polyols or silicone polyols, polyolefin-based polyols and the like are used. It is also possible to use some of the above polyols in combination. Among the polyols, the molecular weight is 300
It is preferably up to 10,000, more preferably 5
It is from 00 to 5,000. Polyester polyols and polycarbonate polyols are suitable as the type of polyol. When a polyol having 3 or more OH groups in one molecule is used, the resulting polyurethane contains a crosslinked structure. Therefore, the amount of the polyol having 3 or more OH groups in one molecule may be selected according to the processability, mechanical properties, surface condition, etc. required for the composite. The amount ratio of the isocyanate compound and the polyol used in the present invention varies depending on the desired physical properties of the composite. The amount ratio of the isocyanate compound and the polyol used in the present invention is NCO group / OH group ratio of 0.5.
-20, preferably 1-5. If the NCO group / OH group ratio is too small, the molecular weight of the polyurethane component will be low, and the physical properties of the composite will not be sufficient. Further, if the NCO / OH ratio is too large, the processability of the composite is deteriorated, which is not preferable. The present invention does not necessarily require a urethanization catalyst. However, to accelerate the reaction, a urethanization catalyst may be used. As the urethanization catalyst, known ones such as organic metals represented by organotin compounds such as dibutyltin laurate and dibutyltin maleate, amines, acetylacetone and the like can be used. The amount is 100 total amount of isocyanate compound and polyol.
It is 2 parts by weight or less with respect to parts by weight. The ratio of vinyl polymer to polyurethane is
It can take any value depending on the physical properties desired for the purpose of use of the composite. Therefore, the amount ratio of the vinyl-based monomer and the polyurethane constituent is set according to the purpose of use. It should be noted that the greater the proportion of polyurethane, the greater the flexibility and elongation. The aqueous medium having a pH of 4 or less according to the present invention is a suspension polymerization known by a method of polymerizing a so-called vinyl monomer,
An acidic substance is added to the aqueous medium used in fine suspension polymerization and emulsion polymerization to make it acidic, and the initial PH value is 4
The following is acceptable. The acidic substance is a mineral acid such as hydrochloric acid, sulfuric acid or phosphoric acid, or an organic acid such as an alkyl sulfonic acid or an aromatic sulfonic acid. The lower limit of PH depends on the material of the polymerization vessel, but if it is too low, it is not effective. The conditions such as the type and concentration of the suspending agent and the emulsifier used here may be known conditions suitable for the vinyl monomer used. The epoxy compound used in the present invention is an organic compound having one or more epoxy groups in the molecule and is effective in improving the thermal stability. As the epoxy compound, various known compounds can be used, but epoxidized soybean oil, epoxidized Amman oil, etc., which are used as plasticizers or heat stabilization aids for vinyl chloride polymers Animal and vegetable oils, epoxidized fatty acid esters such as epoxy stearic acid esters, epoxidized fatty acid esters such as dioctyl epoxy hexahydrophthalate, bisphenol A diglycidyl ether, orthocresol novolac type epoxy resins, epoxies such as hexahydrophthalic acid diglycidyl ester Examples of preferable compounds include resin prepolymers and various epoxidized oligomers such as epoxidized polybutadiene. The amount of the epoxy compound used is 100 parts by weight of the total amount of the isocyanate compound and the polyol.
It is 0.1 to 5 parts by weight. If the amount is less than 0.1 parts by weight, the effect is small, and if the amount is more than 5 parts by weight, the mechanical properties and the like are more adversely affected than the effects. To radically polymerize the vinyl-based monomer, a known radical polymerization catalyst used for polymerizing the vinyl-based monomer may be used. That is, suspension polymerization,
In the case of fine suspension polymerization, organic peroxides soluble in vinyl monomers such as diacyl peroxides, dialkyl peroxides, hydroperoxides, peroxydicarbonates, ketone peroxides, Organic azo compounds such as peroxyesters and azobisisobutyronitrile. In the case of emulsion polymerization,
Water-soluble peroxides such as hydrogen peroxide, potassium persulfate, and ammonium persulfate are used. In the method of the present invention, a polymerization vessel equipped with a stirrer for polymerizing vinyl monomers in an aqueous medium may be used. Using the polymerization vessel, an epoxy compound, an isocyanate compound, a polyol, and, if necessary, a urethane-forming catalyst, a vinyl-based monomer and a radical are dissolved in an aqueous medium in which a suspending agent or an emulsifier is dissolved to adjust the pH to 4 or less. When a polymerization initiator is charged and the polymerization reaction is carried out according to the conditions suitable for the vinyl-based monomer and the radical polymerization initiator to be used, the combined urethanization reaction also proceeds to give a vinyl-based polymer-polyurethane composite. Alternatively, using the polymerization vessel, an epoxy compound, an isocyanate compound, a polyol and, if necessary, a urethanization catalyst are added to an aqueous medium in which a suspending agent or an emulsifying agent is dissolved and a pH is adjusted to 4 or less, and the temperature is kept at room temperature. The urethanization reaction is carried out at about 90 ° C. However, it is not necessary to complete the urethanization reaction. Subsequently, a vinyl-based monomer and a radical polymerization initiator and, if necessary, an aqueous medium is additionally charged, and the polymerization reaction is performed according to conditions compatible with the vinyl-based monomer and the radical polymerization initiator to be used. It becomes a vinyl polymer-polyurethane composite. As a reaction condition in this case, the ratio of the total amount of the vinyl monomer and the raw material of polyurethane / water is about 0.1.
1.5, and other conditions may be known conditions compatible with the vinyl monomer and radical polymerization initiator used. When the vinyl monomer is polymerized, fillers, pigments, various stabilizers, plasticizers, etc., which can be mixed with the vinyl polymer within a range that does not inhibit the polymerization, must be added in advance. Is also possible. According to the present invention, a very dense composite of a vinyl polymer and polyurethane can be obtained. In addition, the polyurethane part can be made into various structures such as NCO group / OH.
Those having a high group ratio, particularly those having a crosslinked structure using a polyisocyanate compound or a polyol having a trifunctional or higher functional number, a compression set or a permanent set having a small composite,
It is possible to obtain a composite having a unique property which cannot be obtained by the conventional vinyl polymer and polyurethane production methods. Moreover, it has excellent thermal stability and is free from coloration due to molding. In addition, the method and apparatus for polymerizing a vinyl-based monomer in an aqueous medium can be used as they are, no extra operation is required for compounding, and productivity is high. Moreover, even if the proportion of the polyurethane component is high, it is possible to obtain a composite having a uniform particle size and few distorted abnormal particles. EXAMPLES The present invention will be illustrated by examples. The measuring methods of the evaluation items in the examples are as follows. -Particle size distribution: JIS Z8801 JIS standard sieve is used for sieving, and the median diameter (Dme) is determined by the Rosin-Rammler equation.
And the equivalent number n was calculated. For this calculation, refer to the item on page 7 [2.3 Rosin-Rammler distribution] of the handbook of powder engineering "Nikkan Kogyo Shimbun, published February 28, 1986". Here, the larger the value of the uniform number n, the narrower the particle size distribution. Preparation of polymer physical property evaluation sample: To 100 parts by weight of the polymer, 3 parts of epoxidized soybean oil, 1.3 parts of calcium stearate, 1.3 parts of zinc stearate were mixed, and 1
Roll kneading was performed at 60 ° C, and press molding was performed at 180 ° C to obtain a sheet. -Permanent elongation: Measured according to JIS K6301. (%) ・ Compression set: Measured at 70 ° C. for 22 hours according to JIS K6301. (%)-Thermal stability: The sheet was put in a Gar oven at 190 ° C. and expressed as the time until the sheet began to turn black. EXAMPLE 1 Hydroxypropylmethyl cellulose (Metronose manufactured by Shin-Etsu Chemical Co., Ltd.) was placed in a stainless steel autoclave equipped with a stirrer.
Dilute sulfuric acid was added to 4000 g of a 0.25 wt% aqueous solution of 65SH50) to make pH 2.1, to which bisphenol A diglycidyl ether 12 g, hexamethylene diisocyanate 160 g, polymethylpentyl glycol adipate (Kurapol P-2010 Kuraray Co., Ltd.): Molecular weight 2000, OH number 57) 1000 g, dibutyltin laurate 0.4 g,
After adding 2 g of azobisisobutyronitrile and degassing under reduced pressure, 1600 g of vinyl chloride monomer was charged. Polymerization was carried out by raising the temperature to 60 ° C. When the pressure in the autoclave dropped to 3 kg / cm ² , the polymerization was stopped and the contents were taken out.
The amount of polymer taken out was 2380 g. The average particle size and particle size distribution of this polymer were measured. The results are shown in [Table 2]. The physical properties of this polymer were evaluated. The results are shown in [Table 2]. Examples 2 and 3 and Comparative Examples 1 and 2 Each amount of hexamethylene diisocyanate, polyol, epoxy compound and vinyl chloride monomer shown in Table 1 and P.
It carried out like Example 1 except having set it as H. The results are shown in [Table 2]. Comparative Example 3 Evaluation was carried out without adding the epoxy compound in Example 3 to obtain a polymer, and the same amount was added to the polymer at the time of preparation of a physical property evaluation sample for evaluation. The results are shown in [Table 2]. Example 4 Using the same autoclave as in Example 1, a 0.25% by weight aqueous solution of hydroxypropylmethylcellulose 4000 was prepared.
Dilute sulfuric acid was added to pH 2.0 to pH 2.0, and 12 g of bisphenol A diglycidyl ether, 160 g of hexamethylene diisocyanate, 1000 g of polymethylpentyl glycol adipate, and 1000 g of dibutyltin laurate were added.
After adding 4 g, the temperature was raised to 60 ° C. and reacted for 1 hour, subsequently 1600 g of vinyl chloride monomer and 2 g of azobisisobutyronitrile were added and polymerization was carried out at 60 ° C. and the pressure in the autoclave was 3 kg / Polymerization was stopped when the content fell to cm ² , and the contents were taken out. The amount of polymer taken out was 23.
It was 00 g. The average particle size and particle size distribution of this polymer were measured. The results are shown in [Table 2]. The physical properties of this polymer were evaluated. The results are shown in [Table 2]. Examples 5 and 6 and Comparative Examples 4 and 5 The amounts of hexamethylene diisocyanate, polyol, epoxy compound and vinyl chloride monomer shown in Table 1 and P.
It carried out like Example 1 except having set it as H. The results are shown in [Table 2]. Comparative Example 6 The epoxy compound in Example 6 was used as a polymer without addition, and the polymer was evaluated by adding the same amount to the polymer at the time of preparation of a sample for evaluating physical properties. The results are shown in [Table 2]. [Table 1] PMPA: Polymethylpentylglycol Acetate PEBA: Poly-ethylenebutyleneglycol aceticate (Molecular weight 200, hydroxyl group 56) Sanester 24620 Sanyo Chemical Co., Ltd. PBA: Poly-ethylenediglycol acetate (Molecular weight 200, Hydroxyl number 5)
6) ADEKA NEW ACE F9-30 Asahi Denka Co., Ltd. BG: Bisphenol A benzyl ether (Sumiepoxy ELA-128 manufactured by Sumitomo Chemical Co., Ltd.) ESCN: Orthocresol Novolak Polyether (Smieffoxy ESCN-1)
95XL) ESBO: Epoxy soybean oil (O-130P manufactured by Asahi Denka Co., Ltd.) [0042] [Table 2]

Continued front page    (72) Inventor Katsujiro Ito             Sumitomo Chemical 5-1, Soukai-cho, Niihama-shi, Ehime             Industry Co., Ltd.

Claims (1)

Claims: 1. A vinyl polymer-polyurethane composite which is subjected to a urethane reaction of an isocyanate compound and a polyol and a radical polymerization reaction of a vinyl monomer in the presence of an epoxy compound in an aqueous medium having a pH of 4 or less. Body manufacturing method. 2. The vinyl monomer is vinyl chloride or a mixture of vinyl chloride and a compound having an unsaturated double bond copolymerizable with vinyl chloride [claim 1]. A method for producing the vinyl polymer-polyurethane composite described. 3. A urethanization reaction between an isocyanate compound and a polyol is carried out in advance, and subsequently a radical polymerization reaction of a vinyl monomer is carried out in the presence of the polyurethane. Method for producing vinyl polymer-polyurethane composite. 4. A method for producing a vinyl polymer-polyurethane composite according to claim 1, wherein the urethanization reaction of the isocyanate compound and the polyol and the radical polymerization reaction of the vinyl monomer are carried out at the same time. Method.