| 摘要 |
The invention describes a foamable thermoplastic mixture, comprising (A) at least one thermoplastic polymer selected from ethylene-vinyl acetate copolymer (EVA), ethylene methyl acrylate copolymer (EMA), ethylene butyl acrylate copolymer (EBA), ethylene-hexene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, polyethylene (PE), polypropylene (PP) and ethylene-propylene copolymer, (B) at least one long chain branched polymer as a foam stabilizer selected from ethylene-vinyl acetate copolymer (EVA), ethylene methyl acrylate copolymer (EMA), ethylene butyl acrylate copolymer (EBA), ethylene-hexene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, polyethylene (PE), polypropylene (PP) and ethylene-propylene copolymer and (C) at least one chemical blowing agent, wherein the long chain branched polymer (B) is present in an amount of 1 to 30 wt. % relative to the total weight of thermoplastic polymer (A) and long chain branched polymer (B), and at least one of the following distinguishing features applies to the thermoplastic polymer (A) and the long chain branched polymer (B): 1) the value of the melt flow index (MFI) of the long chain branched polymer (B) (MFI(B)) is smaller than the MFI value of the thermoplastic polymer (A) (MFI(A)), wherein MFI(B) is a maximum of 50% of MFI(A), 2) the g value of the long chain branched polymer (B) (g(B)) is smaller than the g value of the thermoplastic polymer (A) (g(A)), wherein g(B) is a maximum of 80% of g(A), 3) the polymer type of the long chain branched polymer (B) differing from the polymer type of the thermoplastic polymer (A). The foamable thermoplastic mixture can be injection molded without foaming and is suitable for the production of low-density foams which can be used, for example, as damping materials or foamed membranes. |
| 主权项 |
1. Foamable thermoplastic mixture, comprising
(A) at least one thermoplastic polymers selected from ethylene-vinyl acetate copolymer (EVA), ethylene methyl acrylate copolymer (EMA), ethylene butyl acrylate copolymer (EBA), ethylene-hexene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, polyethylene (PE), polypropylene (PP) and ethylene-propylene copolymer, (B) at least one long chain branched polymer with a g value, determined on the basis of high temperature GPC, as the ratio of the intrinsic viscosity of the polymer to be analyzed to the intrinsic viscosity of the PE-Standard NBS 1475 according to Kulin et al., Pure and Applied Chemistry 1988, 6, (9), p. 1403-1415, of less than 1 as a foam stabilizer selected from ethylene-vinyl acetate copolymer (EVA), ethylene methyl acrylate copolymer (EMA), ethylene butyl acrylate copolymer (EBA), ethylene-hexene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, polyethylene (PE), polypropylene (PP) and ethylene-propylene copolymer and (C) at least one chemical blowing agent,
wherein the long chain branched polymer (B) is present in an amount of 1 to 30 wt. % relative to the total weight of thermoplastic polymer (A) and long chain branched polymer (B), andat least one of the following distinguishing features applies for the thermoplastic polymer (A) and the long chain branched polymer (B): 1) the value of the melt flow index (MFI), determined at 190 ° C. and 2.16 kg according to ASTM D1238, of the long chain branched polymer (B) (MFI(B)) is smaller than the MFI value of the thermoplastic polymer (A) (MFI(A)), wherein MFI(B) is a maximum of 50% of MFI(A), 2) the g value of the long chain branched polymer (B) (g(B)) is smaller than the g value of the thermoplastic polymer (A) (g(A)), wherein g(B) is a maximum of 80% of g(A), 3) the polymer type of the long chain branched polymer (B) differs from the polymer type of the thermoplastic polymer (A). |
