| 摘要 |
1. Method for improving the resistance to degradation by heat and light of vinyl resins having bases on one or more vinyl chloride polymers and/or copolymers, wherein there is added to the resin a stabiliser consisting of a 2,6-dimethyl 1,4-dihydro 3,5-pyridine dicarboxylate having the formula see diagramm : EP0027439,P18,F1 in which R represents a linear alkyl radical with 1 to 22 carbon atoms, an alkynyl or alkenyl linear radical with 3 to 18 carbon atoms, an aralkyl radical possibly substituted in the ortho or para position by a halogen atom or by a methyl or methoxy radical, or a R3 -O-(CH2 )m- radical wherein m assumes the value 2, 3 or 4 and R3 represents a linear alkyl radical with 1 to 4 carbon atoms or a phenyl radical, characterised in that there is also incorporated in the resin a second stabiliser selected from organostannic derivatives satisfying one of the general formulas (R1 )2 Sn(OCOR2 )2 (R1 )2 Sn(SR2 )2 (R1 )2 Sn [S(CH2 )p CO2 R2 ]2 (R1 )2 Sn(C4 H2 O4 ) (C4 H9 Sn)2 S3 in which formulas R1 represents a branched or linear alkyl radical with 4 to 12 carbon atoms, R2 designates a branched or linear alkyl radical with 4 to 18 carbon atoms, and p has the value 1 or 2, and that the said dihydro pyridine and organostannic stabilisers are used in proportions such that the resin contains, per 100 parts by weight of resin, 0.01 to 0.5 part of the dihydro pyridine stabiliser and less than 1 part by weight of organostannic stabiliser, with a total quantity of the said stabilisers of at least 0.2 part by weight. |
