| 摘要 |
<p>1521344 Polyurethanes BAYER AG 2 March 1976 [4 March 1975 18 April 1975] 8257/76 Heading C3R [Also in Division C2] A polyurethane containing structural units of the general formula:- wherein R<1> and R<11>, each represent hydrogen a C1-6 alkyl radical, a C6-15 aryl radical, a C4-12 cycloalkyl radical, halogen, -NO2, -CN, -OR<111> or -COOR<111>, where Roll is a C1-6 alkyl radical, and R represents a linear or branched C1-25 alkylene radical which may optionally contain from 1-12 atoms of N and/or O and/or S in the form of secondary or tertiary amino groups, urea or acid amide groups, ether, urethane or ester groups, thioether, thiourethane or thioester groups, a C4-12 cycloalkylene radical, a C8-15 aralkylene radical, -CH2COCH2-, -CO-CO- or -COCH2CH2CO-, may be prepared by reacting a polyhydroxyl compound having a M.wt. of from 400-10,000, a polyisocyanate and an aromatic diamine of the formula The amino groups are preferably in the ortho, ortho<1> or para, para<1> positions with respect to, the -S-R-S- group. The polyurethanes may be cellular or non-cellular. The polyhydroxyl compounds may be polyesters, polyester-amides, polyethers, polythioethers, polyacetals, polycarbonates or polyamides, many examples of which are given. The polyisocyanates may be aliphatic, cyclo-aliphatic, araliphatic, aromatic or heterocyclic polyisocyanates, examples of which are given. Optional ingredients include foaming agents, e.g. water and/or volatile organic substances; catalysts, e.g. tertiary amines, organotin compounds, silaamines, hexalhydrotriazines, alkali metal hydroxides, phenolates or alcoholates, and tetraalkyl ammonium hydroxides; emulsifiers; foam stabilizers; cell regulators; flame-proofing agents; fillers, plasticizers; fungicides and bacteriocides. The polyurethane may be prepared by the single stage, prepolymer or semi-prepolymer process. Suitable aromatic diamines have the formula where R is -C2H4-O-C2H4-; -(CH2)4-O- (CH2)4-; -C2H4-O-CH2-O-C2H4- -CH2COCH2-; -COCO-; -CH2C6H4- CH2-; -COC2H4CO-; [(CH2)6NHCONCH3]2- (CH2)2; [-(CH2)6NH]2CO; -(CH2)nwhere n = 1-4; -(CH2)2-S-(CH2)2-; and [-(CH2)2OCONH]2(CH2)6. In the Examples polyurethanes are prepared by reacting a prepolymer prepared from a mixture of 2,4- and 2,6-tolylene diisocyanate, or 2,4-tolylene diisocyanate alone, and either a polytetrahydrofuran of M.wt. 1,700 or 2,000, or a polyester of adipic acid, ethylene glycol and butylene glycol (OH number 56), with any one of the following diamines:- 2,21-butylene dithiodianiline; 2,2<1> ethylene dithiodianiline; 2,2<1>-methylene-dithiodianiline; 2,21-xylylene dithiodianine; 4,4<1>- ethylene dithiodianiline; 2,21-diethylene ether dithiodianiline; 2,2<1>-N,N<1>-hexamethylene urea dithiodianiline; and 2,2<1>-acetonylene dithiodianiline. The reacting mixture is introduced into a preheated mould. The casting is subsequently removed from the mould and tempered at elevated temperature.</p> |
