BETA NUCLEATOR FOR POLYPROPYLENE
Publication Date: 2004-Sep-02
The IP.com Prior Art Database
Isotactic polypropylene is known to exist in several different crystal phases. The most common of these phases is the alpha phase. However, under certain conditions another crystal phase, the beta phase, can occur. This invention relates to the use of zinc adipate as an additive that can cause polypropylene to preferentially form the beta phase. In this invention, zinc adipate is melt homogenized with polypropylene. When the polypropylene is then cast or molded, a large fraction of the polymer will form the beta phase, which has a different melting point than the more usual alpha phase. Products with beta crystallinity can exhibit much higher impact resistance than those with alpha crystallinity. They can also be used to produce micro-porous films.