Browse by author
Lookup NU author(s): Emeritus Professor Jim White,
Dr Ian Craig
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Chain scission and crosslinking concentrations have been derived from molecular weight distributions obtained by gel permeation chromatography after three weeks and six weeks laboratory ultraviolet (UV) exposure on samples taken at different depths from the exposed surfaces of 3mm thick injection molded bars made from LDPE, LLDPE and HOPE. Degradation was rapid near the exposed surfaces but very little change occurred in the bar centers, due to oxygen starvation. The most rapid rises in scission and crosslink concentrations were observed with LDPE, for which the concentrations after 6 weeks exposure were approximately double those measured after 3 weeks. With LLDPE and HOPE the scission and crosslink concentrations after 6 weeks exposure were much greater than twice those after 3 weeks. Scission dominated over crosslinking at all depths and for all materials and was always ≥3, with a value of ∼9 recorded for HOPE near the exposed surface after 6 weeks exposure.
Author(s): White JR, Craig IH, Shyichuk AV, Syrotynska I
Publication type: Conference Proceedings (inc. Abstract)
Publication status: Published
Conference Name: Annual Technical Conference Proceedings
Year of Conference: 2004
Publisher: Society of Plastics Engineers, SPE