Patent ID: 6376586
Filing Date: 2002-04-23
Classification: C08K,C08L

Abstract:
A flexible, tough polymer composition, comprising:a) a polymer A, being at least one of: i) at least one homopolymer of vinylidene fluoride (VF2), and ii) a copolymer of VF2 and at least one other monomer copolymerizable with VF2, in which the at least one other monomer is present in an amount of between 0 and 30 parts by weight per 100 parts by weight of VF2; b) at least one elastomer B, present in an amount from 1.5 to 5 parts by weight per 100 parts by weight of A; and c) at least one plasticizer C, present in an amount from 2.5 to 5 parts by weight of C per 100 parts by weight of polymer A, the plasticizer being selected from the group consisting of dibutyl sebacate and N-n-butylsulphonamide; wherein the sum of elastomer B and plasticizer C comprises from 4 to 10 parts by weight per 100 parts by weight of polymer A, wherein the polymer A has a melt flow index, according to the ISO 1133 standard at 230Â° C. under a load of 5 kg, of from about 0.14 to about 0.8 g/10 minutes, and a critical modulus GC, at the intersection of the melt shear moduli Gâ€² and Gâ€³ measured at 190Â° C., of between 10 and 21 kPa, and wherein the flexible, tough polymer composition has the following properties: a resistance to flexural rupture on a sleeved metal tape of greater than 70%; a weight loss &Dgr;w in air at 150Â° C. for 1 month of less than or equal to 8% and a weight change &Dgr;p in petroleum (an equal-volume mixture of cyclohexane, isooctane and xylene) at 150Â° C. for 1 month which is not negative; an elongation at the yield point, &egr;Y, of greater than 11%, according to the ISO 180-1982 standard; an elongation at break Eb of greater than 200%, according to the ISO 180-1982 standard; an impact strength at 23Â° C. of greater than 50 kJ/m2, according to the ISO 180-1982 standard; and an impact strength at âˆ’30Â° C. of greater than 10 kJ/m2, according to the ISO 180-1982 standard.