Case for valve-regulated lead-acid batteries

摘要

A case for valve-regulated lead-acid battery comprising an olefin polymer composition comprising:
A) From 60 wt % to 95 wt %, of a propylene homopolymer, or a copolymer of propylene containing 3% or less of ethylene, said homopolymer or copolymer having a Polydispersity Index (P.I.) value of from 4.6 to 10 and a fraction insoluble in xylene at 25° C., higher than 98 molar %; andB) from 5 wt % to 40 wt %, of a copolymer of propylene and ethylene containing from 30 wt % to 65 wt % of ethylene derived units;

the sum A)+B) being 100.

主权项

1. A case for valve-regulated lead-acid battery comprising an olefin polymer composition consisting essentially of:
A) from 85 to 91 wt % of a propylene homopolymer, or a copolymer of propylene containing 3% or less of ethylene, said homopolymer or copolymer having a polydispersity index (P.I.) value of from 5.1 to 8 and a fraction insoluble in xylene at 25° C. of 98.4 molar %; and B) from 9 to 15 wt % of a copolymer of propylene and ethylene containing from 30 wt % to 65 wt % of ethylene derived units;
wherein the sum of the wt % amounts of A)+B) is 100,wherein the olefin polymer composition has a flexural modulus according to ISO 178 at 23° C. from 1922 to 2500 MPa and at 90° C. from 525 to 1000 MPa,wherein the MFR measured according to ASTM D 1238, condition 1, 230° C., 2.16 Kg of component A) ranges from 1.5 g/10 min to 5.0 g/10 min.