TITLE:
Dielectric and Electric Modulus Behavior of Chlorinated Poly(Vinyl Chloride) Stabilized with Phenyl Maleimide
AUTHORS:
Taha A. Hanafy
KEYWORDS:
CPVC; Stabilizer; Plasticizer; Dielectric Relaxation; Hopping Conduction
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.2 No.4,
December
31,
2012
ABSTRACT: Dielectric constant, ε', dielectric loss factor, ε",
electric modulus, M, and ac conductivity, σac, of pure CPVC and that
stabilized with 10 wt% of phenyl maleimide, PM, have been carried out. The
dielectric properties have been studied in the temperature and frequency
ranges; 310 K - 450 K and 1 kHz- 4 MHz, respectively. The incorporation of 10 wt% of PM
as stabilizer for CPVC leads to reduce its Tg from 405K to 378K at 10
kHz. PM molecules within CPVC structure reduce the double bond, stabilizer
effect, and cause the widely spacing between CPVC main chains, plasticizer
effect. Three dielectric relaxation
processes namely ρ, α', and α were observed for pure CPVC. The first process
was explained based on space charge formation or Maxwell-Wagner-Sillers, MWS,
polarization. The second one is due to the segmental motion of the branching of
CPVC. The third process occurs around the glass-rubber temperature, Tg,
and is related to the micro-Brownian motion of the main polymer chain. Electric
modulus and ac conductivity reveal that the conduction mechanism of CPVC is
follow the correlated barrier hopping, CBH, while stabilized sample exhibits a
quantum mechanical tunneling, QMT, type conduction.