Crystal structures and orientation development in tubular film extrusion of syndiotactic polypropylene and isotactic polypropylene

2001 ◽  
Vol 41 (10) ◽  
pp. 1743-1751 ◽  
Author(s):  
Dongman Choi ◽  
James L. White
Keyword(s):  
Crystal Structures ◽  
Isotactic Polypropylene ◽  
Syndiotactic Polypropylene ◽  
Film Extrusion

The influence of crystal structures of nucleating agents on the crystallization behaviors of isotactic polypropylene

2006 ◽  
Vol 285 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Wei-Min Hou ◽  
Gang Liu ◽  
Jian-Jun Zhou ◽  
Xia Gao ◽  
Yan Li ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Isotactic Polypropylene ◽  
Nucleating Agents ◽  
Crystallization Behaviors

Influence of Morphology on Electrical Properties of Syndiotactic Polypropylene Compared with Those of Isotactic Polypropylene

1999 ◽  
Vol 38 (Part 1, No. 6A) ◽  
pp. 3580-3584 ◽  
Author(s):  
Dong Wook Kim ◽  
Katsumi Yoshino ◽  
Takeo Inoue ◽  
Masaru Abe ◽  
Nobutaka Uchikawa
Keyword(s):  
Electrical Properties ◽  
Isotactic Polypropylene ◽  
Syndiotactic Polypropylene

scholarly journals ChiralAnsaMetallocenes with Cp Ring-Fused to Thiophenes and Pyrroles:  Syntheses, Crystal Structures, and Isotactic Polypropylene Catalysts  [J.Am. Chem. Soc.2001,123, 4763−4773]. 

2001 ◽  
Vol 123 (28) ◽  
pp. 6964-6964 ◽  
Author(s):  
John A. Ewen ◽  
Michael J. Elder ◽  
Robert L. Jones ◽  
Arnold L. Rheingold ◽  
Louise M. Liable-Sands ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Isotactic Polypropylene

scholarly journals Systematic Investigation on the Structure-Property Relationship in Isotactic Polypropylene Films Processed via Cast Film Extrusion

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1636 ◽  
Author(s):  
Federico Di Sacco ◽  
Markus Gahleitner ◽  
Jingbo Wang ◽  
Giuseppe Portale
Keyword(s):  
Isotactic Polypropylene ◽  
Single Site ◽  
Random Copolymers ◽  
Minor Effect ◽  
Structure Property ◽  
Melt Temperature ◽  
Film Extrusion ◽  
Line Speed ◽  
Cast Film ◽  
Roll Temperature

The effect of cast film extrusion processing conditions, such as the chill-roll temperature, temperature of the melt, and line speed, on the structure of different isotactic polypropylene homo- and random copolymers has been investigated by means of Small- and Wide-Angle X-ray Scattering (SAXS and WAXS) and correlated to stiffness and haze. Stiffness and transparency have been found to be strongly dependent on the temperature of the chill-roll. Interestingly, line speed has been found to affect the total crystallinity when the chill-roll temperature is increased, while an overall minor effect of the melt temperature was found for all cast films. The polymer characteristics, defined by the catalyst nature and comonomer content, affect the final material performance, with the single-site catalyzed grades performing better in both mechanics and optics. Haze levels were found to correlate with the mesophase content rather than to α-crystallinity and to be dependent on the domain size for all grades. The remarkably low haze levels reached by the single-site grade with higher isotacticity can arise from high nucleation rate and orientational effects, which ultimately yield smaller and smoother scattering domains.

Sign in / Sign up

Export Citation Format

Share Document