| 簡(jiǎn) 介： |
Polypropylene (PP) is a fast growing commodity resin as it possesses many beneficial
properties such as low density, high stiffness, good resistance to chemicals, and an
easy processability. The conventional PP consists of linear molecules, the molar mass
of which can be varied in a wide range resulting in different flow properties. Introducing
long-chain branches (LCB) adds particular rheological properties to the material which
are advantageous for processing operations like thermoforming or foaming. Special
rheological measurements can be used to assess the behaviour of PP with respect to
these applications which are dominated by elongational flow. Moreover, rheological
experiments are a powerful tool to get an insight into the molecular structure of
polypropylenes, particularly, in the case of long-chain branching. |
