Results 291 to 300 of about 178,590 (332)

Stability of a Blown Film Extrusion Process

International Polymer Processing, 1999
Abstract The stability of a blown film extrusion process has been investigated using a simple isothermal Newtonian model. Although the Newtonian model may be an oversimplification for polymer melts, it serves as a reasonable first approximation for linear polymers (e.g., linear low density polyethylene) in extensional flow situations ...
K.-S. Yoon, C.-W. Park
openaire   +1 more source

Studies on blown film extrusion. III. Bubble instability

Journal of Applied Polymer Science, 1975
AbstractAn experimental study has been carried out to investigate flow instabilities in blown film extrusion. Two types of flow instabilities were observed, depending on whether a bubble was under uniaxial or biaxial stretching. Under biaxial stretching, the phenomenon of a surface wave‐type instability was observed, yielding wavy bubble shapes which ...
Chang Dae Han, Jong Yoo Park
openaire   +1 more source

Blown Film Extrusion Optimization-Control and Screws

Journal of Plastic Film & Sheeting, 1991
On-line film gauging, gravimetric feeding, innovations in blown film dies and wind-up equipment, and improved data handling have made pos sible the production of blown film to higher quality standards. However, ade quate cost control and effective material utilization will require even greater uniformity of the process and property performance of the ...
E.W. Veazey, N. Barrera
openaire   +1 more source

Improving the rheology of linear low-density polyethylene (LLDPE) and processability of blown film extrusion using a new binary processing aid

International polymer processing, 2023
To improve the processability of LLDPE, a binary processing aid composed of polyethylene glycol (PEG) and hydrocalumite was designed. Hydrocalumite containing HPO32− was successfully synthesized with co-precipitation of calcium and aluminum hydroxide in ...
Sarah Ramezan-Nejad, S. Mohamadi, N. Sharifi-Sanjani   +2 more
semanticscholar   +1 more source

Foam Extrusion of Polystyrene Blown with HFC-134a

Cellular Polymers, 2002
There is much interest in developing industrial processes to manufacture extruded polystyrene foam that do not involve ozone depleting blowing agents. A popular alternate candidate is HFC-134a. It has a zero ozone depletion factor and is nearer in chemical structure to standard blowing agents (CFC-22 and HCFC-142b) than carbon dioxide.
Richard Gendron, Michel Huneault, Jacques Tatibouët, Caroline Vachon   +3 more
openaire   +1 more source

Lldpe Resins for High Output Blown Film Extrusion

Journal of Plastic Film & Sheeting, 1991
We take a closer look at the output rate improvements which can be achieved as a result of the improved melt strength of 0.5 MI resins.
D.L. Cooke, M. Koyich
openaire   +1 more source

Blown Film Extrusion of Post-Consumer Recycled Lldpe Film

Journal of Plastic Film & Sheeting, 1993
In this work, the properties of blown film made from post consumer recycled material were studied. Post-consumer recycled LLDPE film was blended with a virgin LLDPE resin at several levels in a twin-screw ex truder, and the melt index, storage modulus, and loss modulus of these blends were measured.
S.J. Hebert, C. Tzoganakis, J. Perdikoulias   +2 more
openaire   +1 more source

Optimized cooling and gauge tolerances in blown film extrusion

Polymer Engineering & Science, 1997
AbstractNumerical calculations of the air flow and heat transport processes in film blowing have been made, considering the turbulence of the air flow. The parameters air mass flow, air temperature, air velocity, and angle‐of‐attack have been varied. The results have shown that the air massflow has the strongest influence on cooling in the processing ...
B. Feron, D. Wolf, J. Wortberg
openaire   +1 more source

Mechanical and Tribological Characterization of Microporous Low Density Polyethylene Films Obtained in Blown Extrusion

Advances in Science and Technology Research Journal
Foaming processes for polymeric materials are usually carried out using extrusion and injection methods. This applies primarily to products whose wall thickness is at least 4 mm.
A. Tor-Świątek, B. Samujło
semanticscholar   +1 more source

Blown Film Extrusion of LLDPE/LDPE Blends

Journal of Reinforced Plastics and Composites, 1999
An experimental study was carried out to investigate the effect of LLDPE/LDPE blend compositions on the physical properties of blown films and processing properties during extrusion. Spiral mandrel die analysis was also performed by FAN method and its results were compared with measured die pressure.
openaire   +1 more source