Mastering PE properties by dual site catalyst in staged polymerisation
| Title |
Mastering PE properties by dual site catalyst in staged polymerisation |
| Publication year |
2002 |
| Language |
English |
| Author |
Follestad, Arild (Norner) |
| Co-Authors |
Eggen, Svein |
| Source |
Nordic Polymer Days May, 2002 |
| Abstract |
Making low density polyethylene in two-stage low pressure polymerisation processes gives potential for enhanced processing behaviour and end-use polymer properties. This is achieved by optimising molecular weight and comonomer content of two components. A two-stage process which has the higher comonomer level in the last reactor, can even make a copolymer which has one component (the lower molecular weight) with zero comonomer. This is extremely beneficial for many applications. To improve the polyethylene products further, this process can be combined with polymerisation catalysts which have at least two ('dual site') or more different types of active sites. This creates complete control over the molecular weight distribution, extending the potential for further improvements in polymer properties. For instance, vast increase of melt strength can be achieved, as well as reduced tendency to nonwanted polymeric gels. |