𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Influence of long chain branching on extrudate swell of low-density polyethylenes

✍ Scribed by L. A. Hamielec; J. Vlachopoulos

Publisher
John Wiley and Sons
Year
1983
Tongue
English
Weight
234 KB
Volume
28
Category
Article
ISSN
0021-8995

No coin nor oath required. For personal study only.

✦ Synopsis

An experimental study of extrudate swell has been carried out, involving five low-density polyethylene (LDPE) samples of approximately the same molecular size but of different frequencies of long-chain branching (LCB). The results show that the samples with higher frequencies of LCB exhibit a tendency to swell more than samples of lower frequency. This tendency is more pronounced for short LID dies and high shear rates. It seems possible that LDPE samples of varying LCB frequencies can be differentiated by determining the swelling ratio @ID) with orifice dies (LID N 0) a t high throughput rates.

πŸ“œ SIMILAR VOLUMES

Sizes of long branches in low density po
Sizes of long branches in low density polyethylenes
✍ Daniele C. Bugada; Alfred Rudin πŸ“‚ Article πŸ“… 1987 πŸ› John Wiley and Sons 🌐 English βš– 335 KB πŸ‘ 1 views

13C-NMR spectroscopy and size exclusion chromatography have been used to determine the mean length of long branches in a number of high pressure process low density polyethylenes (LDPEs). 13C-NMR analyses count all branches longer than C5 as "long." The polyethylenes studied all had 2-3 long branche

Blends of high-density polyethylene with
Blends of high-density polyethylene with homogeneous long-chain branched polyethylenes
✍ JΓΌrgen Schellenberg πŸ“‚ Article πŸ“… 1997 πŸ› John Wiley and Sons 🌐 English βš– 246 KB πŸ‘ 1 views

With the recent development of new catalysts based on specific metallocenes, ethylene polymers with a narrow molecular weight distribution and comonomers placed homogeneously in the polymer chain have been accessible. In particular, bridged amido complexes can be used to integrate defined long-chain

Sizes of long-chain branches in a high-p
Sizes of long-chain branches in a high-pressure low-density polyethylene as a function of molecular weight
✍ Takao Usami; Yukitaka Gotoh; Sigeru Takayama πŸ“‚ Article πŸ“… 1991 πŸ› John Wiley and Sons 🌐 English βš– 307 KB πŸ‘ 2 views

## SYNOPSIS The mean length and the indices of long-chain branches (LCBs) of a high-pressure lowdensity polyethylene (HPLDPE) as a function of molecular weight have been determined for its molecular-weight-fractionated parts by the I3C-NMR analysis and the viscosity measurements. The mean LCB leng