Rheology studies of polyethylene/chemical blowing agent solutions within an injection molding machine.: An article from: Polymer Engineering and Science

This digital document is an article from Polymer Engineering and Science, published by Thomson Gale on August 1, 2005. The length of the article is 5889 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser.

From the author: An in-line capillary rheometer nozzle equipped to a conventional reciprocating 55-ton injection molding machine was used to study the viscosity of single phase low density polyethylene (LDPE)/chemical blowing agent (CBA) solutions under high shear rate in the concentration range of 0 to 5 wt%. The steady shear viscosity of LDPE with endothermic and exothermic chemical blowing agents was measured for shear rates ranging from 170 to 200,000 [s.sup.-1] and under pressure conditions up to 36 MPa. Pressure-volume-temperature (pvT) measurements were determined to account for the pressure effects and the changes of the free volume during processing. The viscosity reduction of the polymer-CBA solution was found to be dependent on the concentration of the chemical blowing agent and melt pressure. A model based on a simplified Cross-Carreau model, incorporating the pvT behavior of LDPE, and the free volume concept was proposed to estimate the viscosity reduction resulting from the addition of a chemical blowing agent. The model employs a scaling method based on concentration-dependent and pressure-dependent shift factors to collapse the viscosity measurement to a master curve at each temperature. POLYM. ENG. SCI., 45: 1108-1118, 2005. [c] 2005 Society of Plastics Engineers

Citation Details
Title: Rheology studies of polyethylene/chemical blowing agent solutions within an injection molding machine.
Author: X. Qin
Publication:Polymer Engineering and Science (Magazine/Journal)
Date: August 1, 2005
Publisher: Thomson Gale
Volume: 45 Issue: 8 Page: 1108(11)

Distributed by Thomson Gale