JPS633904B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing polyurethane elastomers. More specifically, it is a composition whose main component is a prepolymer having an isocyanate group at the molecular end (hereinafter referred to as the main component), and a cured composition containing a crosslinking agent, a plasticizer, and, if necessary, fillers, catalysts, and various other additives. The present invention relates to a method of manufacturing a polyurethane elastomer by incorporating an organic polymer into the curing agent (hereinafter referred to as a curing agent) and using a curing agent with low viscosity and good dispersibility. The water-cured elastomer produced by the method of the present invention is suitable for use as general elastomers, waterproofing materials, sealing materials, flooring materials, gland materials, coating materials, and the like. Conventionally, polyurethane flooring and waterproofing materials are used by mixing a base material and a hardening agent and applying the mixture to a base slag such as concrete or mortar during construction. At this time, the viscosity of the base agent and curing agent greatly influences the workability. In particular, since an inorganic filler is mixed into the curing agent, the thixotropy is large, and in many cases, the unevenness of the coating surface does not disappear after application and hardens without becoming smooth. However, when the viscosity of the hardening agent is lowered, the filler settles, creating problems in construction. In particular, in water-curable urethane elastomers that use water instead of conventional polyamines, polyols, etc. as crosslinking agents for the curing agent to obtain non-foaming elastomers, the viscosity of the curing agent is extremely low due to the high affinity between water and filler. There was also a tendency for the filler to become blocked depending on the amount of water added. In contrast, various anti-settling agents or dispersants are commercially available, but none have overcome these drawbacks. The present invention has been accomplished by discovering a method for overcoming these drawbacks and providing good physical properties of a coating film with a reinforcing effect superior to that of conventional fillers. That is, in the present invention, when forming a polyurethane elastomer by mixing a composition mainly composed of a prepolymer having an isocyanate group at the molecular end and a cured composition containing a crosslinking agent and a plasticizer, This is a method for producing a polyurethane elastomer, which is characterized by adding 0.5 to 50% by weight of an organic polymer having a particle size of 35 mesh or less to the polyurethane elastomer. The organic polymer particles used in the present invention include powders such as polyvinyl chloride, polypropylene, polyvinyl acetate, polystyrene, acetalized products or ketalized products of polyvinyl alcohol, and crushed products of these resins, and the number is 35 mesh or less, preferably 200 mesh.
It is below Metsushiyu. These organic polymer particles may be used alone or in combination of two or more types in an appropriate ratio. In this case, if it becomes 35 meshes or more,
The surface of the elastomer becomes rough, which is undesirable. The amount of these organic polymer particles used is preferably 0.5 to 50% by weight (hereinafter simply referred to as %) in the curing agent, preferably 5 to 20%. If it is less than 0.5%, the desired purpose will not be achieved, and if it exceeds 50%, the physical properties of the coating will deteriorate. The main ingredient is usually an active hydrogen-containing compound and an organic polyisocyanate with an NCO/OH (equivalence) of 1.5 or less.
Obtained by reaction at 150°C, preferably 50 to 100°C,
1-20% isocyanate group at the end, preferably 2-20%
It has 9%. Polyether polyols, polyester polyols, and the like are used as such active hydrogen-containing compounds. Examples of polyether polyols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, dipropylene glycol, trimethylene glycol,
1, 4- or 1, 3-butylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, decamethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, sucrose, aconitic acid, trimellitic acid, hemimellitic acid, ethylene diamine, propylene diamine,
diethylenetriamine, triethanolamine,
Birogallol, dihydrobenzoic acid, hydroxyphthalic acid, resorcinol, hydroquinone, bisphenol A (2,2-bis(4'-hydroxyphenyl)propane), bisphenol F (4,4'-dihydroxydiphenylmethane), One or more compounds having at least two or more active hydrogen atoms in the molecule, such as 1,2-propanedithiol, and one or more of ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide, etc. An addition polymer obtained by adding is used. Examples of polyester polyols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, dipropylene glycol, trimethylene glycol, 1,4- or 1,3-butylene glycol,
One or more compounds having at least two hydroxyl groups in the molecule, such as tetramethylene glycol, neopentyl glycol, hexamethylene glycol, decamethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, etc. Malonic acid, maleic acid, succinic acid, adipic acid, tartaric acid, pimelic acid, sebacic acid, oxalic acid, phthalic acid, terephthalic acid, hexahydrophthalic acid, aconitic acid, trimellitic acid, hemimelittic acid, etc. In both cases, a condensation polymer of one or more compounds having two carboxyl groups is used. In addition, active hydrogen-containing compounds include ring-opening polymers of cyclic esters such as polycaprolactone, and furthermore, ethylenically unsaturated monomers or polymers of these monomers are grafted in the presence of a radical initiator in polyether polyols. Polymer polyl obtained by polymerization, 1,2-polybutadiene glycol, 1,4
-Compounds such as polybutadiene glycols may also be used. The above-mentioned polyether polyols, polyester polyols, or other active hydrogen compounds can be used alone or as a mixture of two or more. Examples of the organic polyisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, a mixture of 2,4 and 2,6-tolylene diisocyanate (65/35, 80/20), and 4-tolylene diisocyanate.
4'-diphenylmethane diisocyanate, m-phenylene diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate ester, 1,4-cyclohexylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 3,3 '-dimethyl-4・
4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 3,3'-dichloro-4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 1 -5-tetrahydronaphthalene diisocyanate etc. are used. Crude products of tolylene diisocyanate and 4,4'-diphenylmethane diisocyanate and modified products such as carbodiimide-modified 4,4'-diphenylmethane diisocyanate can also be used. The above organic polyisocyanates may be used alone or as a mixture of two or more. The main ingredient may be a prepolymer alone or may contain a solvent or plasticizer as a thinning agent. The amount of thinner used is 40% or less of the base agent. As the crosslinking agent in the curing agent, water, polyamine, and polyol can be used alone or in combination of two or more. The amount of crosslinking agent used is 3 to 50% of the hardening agent.
% is preferably 5 to 30%. Examples of polyamines include ethylenediamine, hexamethylenediamine, piperazine, p-
xylene diamine, p-phenylene diamine,
1,4-diaminocyclohexane, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4.
4'-diaminodiphenylmethane, 3.3'-diethyl-4.4'-diaminodiphenylmethane, 3.
3'-dichloro-4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,
Esters (dimethyl form, diethyl form, diisopropyl form) of 4'-methylene dianthranilic acid, etc. are used. As the polyol in the curing agent, the polyols exemplified in the section of the main ingredient are used. The base resin and the curing agent are reacted at an isocyanate group/active hydrogen (equivalent ratio) of 0.005 to 2.0, preferably 0.02 to 1.5. The carbon dioxide absorbent used in the curing agent in the present invention is a hydroxide or oxide, or basic salt, complex salt, or double salt of a metal belonging to Groups 2, 3, or 4 of the Periodic Table of the Elements. Basic metal hydroxides such as calcium oxide, barium hydroxide, and magnesium hydroxide, metal oxides such as quicklime and barium oxide, and cements such as Portland cement can be used. It is also possible to use these in combination. These carbon dioxide absorbers account for 5 to 50%, preferably 10 to 30%, of the curing agent. The fillers used in the present invention include conventionally known fillers such as calcium carbonate, talc, clay, silica, carbon black, and titanium oxide, and the amount of fillers used is 0 to 55% of the hardening agent. Organic liquids include coal tar, dioctyl phthalate, dibutyl phthalate, dioctyl adipate, chlorinated paraffin, tricresyl phosphate, trioctyl phosphate, and liquefied low polymers of terpene resins (Eurex, Tokyo Jushi Co., Ltd.) ) etc. are used. The amount of organic liquid used is 20-60% in the curing agent. The catalyst used in the present invention is a known catalyst that promotes the urethanization reaction or urea production reaction, such as amines such as triethylenediamine, lead acetate, lead caproate, lead octylate, lead caprate, lead naphthenate, etc. In addition, tin compounds such as dibutyltin dilaurate, dibutyltin di-2-ethylhexoate, etc. are used. These catalysts may be used alone or in combination. As other additives, antifoaming agents, thixotropic agents, ultraviolet absorbers, antioxidants, pigments, etc. may be used as necessary. These curing agents are produced by kneading and dispersing them using a kneader, a sieve, a roll, a sand mill, etc., which are capable of sufficiently uniform mixing. Examples will be shown next, but the present invention is not limited to these examples. In Examples and Comparative Examples, parts are parts by weight. Examples 1 to 5, Comparative Example 1 The composition of the curing agent, the viscosity of the curing agent, and the physical properties of the coating film were
Shown in the table. The curing agent was manufactured by kneading and mixing using three rolls.

【table】

[Table] Examples 6 to 9, Comparative Example 2 The curing agent was coal tar + DOP or DOP + Yurex 170 and 3,3'-dichloro-4,4'-diaminodiphenylmethane (hereinafter referred to as MOCA).
The mixture was melted at 80 to 90°C and kneaded and mixed using three rolls in the same manner as in Example 1. The results are shown in Table 2.

[Table] * Same as Table 1.

Claims (1)

[Claims] 1. When molding a polyurethane elastomer by mixing a composition mainly composed of a prepolymer having an isocyanate group at the molecular end and a cured composition containing a crosslinking agent and a plasticizer, a particle size of 35 Organic polymer particles smaller than mesh size
A method for producing a polyurethane elastomer, characterized by adding 0.5 to 50% by weight.