Curing composition

A curing composition comprising a polymer component and a compatible oligomeric component, the polymer component being a co-polymer of functional silyl group-containing units derived from monomers of Formula (1):

• CH.sub.2 .dbd.CR.sup.1 CO.sub.2 (CH.sub.2).sub.a L Formula (I)
• where a is 2 to 6
• R.sup.1 is hydrogen or methyl and
• L is a group of Formula (II):
• ##STR7## where R.sup.2 is C.sub.1-4 alkoxy, C.sub.2-4 alkoxy--C.sub.2-4 alkoxy, C.sub.1-4 alkanoyl, enolate or oximate, and R.sup.3 and R.sup.4 are C.sub.1-4 alkoxy, C.sub.2-4 alkoxy--C.sub.2-4 alkoxy, C.sub.1-4 alkanoyl, enolate, oximate or C.sub.1-6 alkyl;
• and structural units derived from polymerisable ethylenically unsaturated monomers such that each molecule of the polymer component contains at least two silyl groups of Formula (II);
• the oligomeric component being a compound of Formula (III):
• E(GKL).sub.b Formula (III)
• where b is 3 to 6;
• E is derived from a biuret or isocyanurate oligomer of a di-functional isocyanate, the isocyanate being a C.sub.4-15 aliphatic, cycloaliphatic or aromatic diisocyanate optionally substituted with one or more C.sub.1-6 alkyl groups or is derived from an adduct of C.sub.2-6 aliphatic diol, triol or tetraol and a poly functional isocyanate, the poly functional isocyanate being either a di-functional isocyanate as previously defined or being itself the adduct of an aliphatic triol and a di-functional isocyanate as previously defined,
• G is
• --[O(CH.sub.2).sub.5 CO].sub.c [O(CH.sub.2).sub.d OCO(CH.sub.2).sub.2 ]--
• in which c is 0 to 2, d is 2 to 4;
• K is
• --[NR.sup.5 (CH.sub.2).sub.m ]--
• in which m is 1 to 6, and R.sup.5 is hydrogen, methyl, --(CH.sub.2).sub.n R.sup.6, or --CH.sub.2 CHOH(CH.sub.2).sub.n --R.sup.6 in which R.sup.6 is the group L as defined with reference to Formula (I) and n is 1 to 4.