Record Details

Study of Layered Silicate Clays as Synergistic Nucleating Agent for Polypropylene

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Study of Layered Silicate Clays as Synergistic Nucleating Agent for Polypropylene
 
Creator PRESCHILLA, N
RASHEED, ASA
SAHADEVAN, S
BISWAS, A
BELLARE, JR
SHYAMROY, S
 
Subject isotactic polypropylene
crystallization behavior
mechanical-properties
nano-particles
nanocomposites
composites
morphology
sorbitol
nanoparticles
polymorphism
crystallization
nucleation
organoclay
polypropylene
 
Description Effect of very small quantities of organically modified layered silicate clay on the nucleation of polypropylene (PP), as an additive at ppm levels dosage was investigated, in combination with two of the most commercially exploited organic nucleating agents, one of which is a cyclic aromatic phosphinate salt and the other is bis(3,4-dimethylbenzylidene) sorbitol, each representing a separate class of nucleating molecules by itself. Substitution of a considerable fraction of either of these organic nucleating agents with organically modified inorganic nanoclay was seen to result in a unique synergy between the two in nucleating PP. Polarized light microscopy studies of these synergistic formulations with organoclay to nucleating agent ratios of 1:1 and 1:3 totaling 0.2 weight percent in PP showed significant reduction in spherulite size from that of non-nucleated PP, and compared with the samples containing exclusive organic nucleating agent at similar loading. Differential scanning calorimetric studies provided evidence and insight into such synergistic behavior. Crystallization and supercooling temperatures for the synergistic formulations were comparable for those formulations containing only organic nucleating agents, indicating comparable nucleation efficiency, whereas organoclay alone, although showing some extent of nucleation, was clearly poorer in efficiency. Wide and small angle X-ray scattering studies further explained these observations. An increase in the gamma polytype fraction was seen in samples that contained both organoclay and nucleating agent, pointing to the role of organoclay as a gamma nucleator. Organoclay was found to be completely exfoliated in these synergistic formulations and was seen as well-dispersed, single platelets in the PP matrix. A hybrid network consisting of exfoliated organoclay platelets and organic nucleating agent molecules was proposed, which is more stable and stiffer than the network formed by nucleating agent alone. (C) 2010 . J Polym Sci Part B: Polym Phys 48: 1786-1794, 2010
 
Publisher JOHN WILEY & SONS INC
 
Date 2011-08-16T15:13:09Z
2011-12-26T12:55:00Z
2011-12-27T05:43:30Z
2011-08-16T15:13:09Z
2011-12-26T12:55:00Z
2011-12-27T05:43:30Z
2010
 
Type Article
 
Identifier JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS, 48(16), 1786-1794
0887-6266
http://dx.doi.org/10.1002/polb.22044
http://dspace.library.iitb.ac.in/xmlui/handle/10054/9537
http://hdl.handle.net/10054/9537
 
Language en