Expanded polystyrene (EPS) constitutes a considerable part of thermoplastic waste in the environment in
terms of volume. In this study, this waste material has been utilized for blending with silica-reinforced
natural rubber (NR). The NR/EPS (35/5) blends were prepared by melt mixing in a Brabender Plasticorder.
Since NR and EPS are incompatible and immiscible a method has been devised to improve compatibility.
For this, EPS and NR were initially grafted with maleic anhydride (MA) using dicumyl peroxide (DCP) to
give a graft copolymer. Grafting was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy.
This grafted blend was subsequently blended with more of NR during mill compounding. Morphological
studies using Scanning Electron Microscopy (SEM) showed better dispersion of EPS in the
compatibilized blend compared to the noncompatibilized blend. By this technique, the tensile strength,
elongation at break, modulus, tear strength, compression set and hardness of the blend were found to be
either at par with or better than that of virgin silica filled NR compound. It is also noted that the thermal
properties of the blends are equivalent with that of virgin NR. The study establishes the potential of this
method for utilising waste EPS
Waste latex products are converted to a processabto material by a novel
economical process developed in our laboratory , It contains rubber hydrocarbon
of very high quality and Is lightly cross -linked. Styrene-butadlene
rubber is mixed with latex reclaim In different proportions . The mechanical
properties are found to be improved up to 60 percent replacement of
styrene-butadlene rubber by latex reclaim . The curing of styrene-butadiene
rubber Is found to be accelerated by the addition of latex reclaim. The
processablllty study shows that the blends can be processed similar to
SBRINR blends.
Rani, Joseph(John Wiley & Sons, Inc., March 20, 2000)
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Abstract:
ABSTRACT: Zinc salts of ethyl, isopropyl, and butyl xanthates were prepared in the
laboratory. They were purified by reprecipitation and were characterized by IR, NMR,
and thermogravimetric analysis techniques. The melting points were also determined.
The rubber compounds with different xanthate accelerators were cured at temperatures
from 30 to 150°C. The sheets were molded and properties such as tensile strength,
tear strength, crosslink density, elongation at break, and modulus at 300% elongation
were evaluated. The properties showed that all three xanthate accelerators are effective
for room temperature curing.