Patent ID: 6303677
Filing Date: 2001-10-16
Classification: C08G,C08L,C09D,C09K,Y02A,Y10S,Y10T

Abstract:
A biodegradable thermoplastic molding composition T4 obtained by mixingh.sub.1) from 99.5 to 0.5% by weight of a polyester Q2, andh.sub.2) from 0.5 to 99.5% by weight of a hydroxycarboxylic acid compound B1 of formula Ia or Ib, ##STR2##wherein p is an integer of from 1 to 1500, r is an integer of from 1 to 4, and G is phenylene, --(CH.sub.2).sub.n --,--C(R)H-- or --C(R)HCH.sub.2 --, n is an integer of from 1 to 5, and R is methyl or ethyl,whereinQ2 is a polyester having a molecular weight (M.sub.n,) of from 6000 to 60,000 g/mol, a viscosity number of from 30 to 350 g/ml (measured in 50:50 w/w o-dichlorobenzene/phenol at a concentration of 0.5% by weight of Q2 at 25.degree. C.), and a melting point of from 50 to 170.degree. C., and being obtained by reacting a mixture consisting essentially ofd.sub.1) from 95 to 99.9% by weight of a polyester PWD or P1, or a mixture of PWD and P1,d.sub.2) from 0.1 to 5% by weight of a diisocyanate C1, andd.sub.3) from 0 to 5 mol %, per mole of component a.sub.1) of the polyester PWD and/or P1, of a compound D having at least three groups capable of ester formation,PWD is a polyester having a molecular weight (M.sub.n) of from 5000 to 50,000 g/mol, a viscosity number of from 30 to 350 g/ml (measured in 50:50 w/w o-dichlorobenzene/phenol at a concentration of 0.5% by weight of PWD at 25.degree. C.), and a melting point of from 50 to 170.degree. C., and being obtained by reacting a mixture consisting essentially ofa.sub.1) a mixture consisting essentially offrom 45 to 80 mol % of adipic acid or ester-forming derivatives thereof or mixtures thereof, from 20 to 55 mol % of terephthalic acid or ester-forming derivatives thereof or mixtures thereof, andfrom 0 to 5 mol % of a sulfonate compound the sum of the individual mole percentages being 100 mol %, anda.sub.2) a dihydroxy compound selected from the group consisting of C.sub.2 -C.sub.6 -alkanediols and C.sub.5 -C.sub.10 o-cycloalkanediols,in a molar ratio of a.sub.1) to a.sub.2) of from 0.4:1 to 1.5:1; andP1 is a polyester having a molecular weight (M.sub.n) of from 5000 to 50,000 g/mol, a viscosity number of from 30 to 350 g/ml (measured in 50:50 w/w o-dichlorobenzene/phenol at a concentration of 0.5% by weight of P1 at 25.degree. C.), and a melting point of from 50 to 170.degree. C., and being obtained by reacting a mixture consisting essentially of a.sub.1), a.sub.2), anda.sub.3) from 0.01 to 5 mol %, per mole of a.sub.1), of a compound D;wherein the molar ratio of a.sub.1) to a.sub.2) is from 0.4:1 to 1.5:1.