Rubbery elastomer-forming room temp.-crosslinkable compsns. - contg. silyl end-substd. polyoxyalkylene- polyether and silane or polysiloxane crosslinking agent

摘要

Room temp.-crosslinkable compsns. contain (A) 100 pts. wt. polyoxyalkylene polyether, silyl gp.-substd. at both ends and having formula (R1)3-a Si(OH)a O-Si(R')2-b(OH)b m -CH2CH2-R2-(OR3)-nOR2-CH2CH2-(Si(R1)2-b(OH)b m-Si(OH)a(R1)3-a (I) (where R1 is opt. substd. monovalent hydrocarbyl or triorganosiloxy; R2 is 1-20 C divalent hydrocarbyl; R3 is pref. 1-4 C divalent hydrocarbyl, esp. -C3H6-; a is o, 1, 2 or 3; b is 0, 1 or 2; a + b is +ve integer =3; m is 0, 1 or 2 and n is a +ve integer) and average mol. wt. 400-15000, or partial condensn. prods. thereof, and (B), as crosslinking agent for (I), 1-30pts. wt. organosilane or organopolysiloxane having formula R4dYe SiO(4-d-e)/2 (II) (where R4 is monovalent hydrocarbyl; Y is a hydrosable gp.; d is 0 or a +ve integer =2 and e is a +ve integer =4, where d+e is a +ve integer =4, and the mol. contains =2 hydrolysable Y gps.). Compsns. form rubbery elastomers and can be used as sealants, compression moulding and food packaging materials.