Thomas,E V; Dr.Joseph,Francis D(Cochin University of Science And Technology, April , 1985)
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Abstract:
Although the physical and technological properties
of modified rubbers were compared with those of conventional
rubbers in the earlier studies reviewed above, the extent of
energy saving possible by their use has not been quantified.
In the present work it is proposed to determine the energy
saving possible by using the following forms of natural rubber:
1. Oil extended natural rubber, 2. peptised natural rubber,
3. latex stage compounds. The process of production and
quality control of the above types of processed rubbers are
proposed to be standardised. It is also planned to work out
a methodology for utilising field coagula for production of
constant viscosity rubbers. The variation in processing
properties of rubber from popular Indian clones will be examined and those with energy advantages in the processing
stage will be identified. In conclusion a recommendation for
adoption of a commercially advantageous processing procedure
among Indian rubber plantation industry is also given.
Description:
Polymer science & rubber technology, Cochin University of Science And Technology
Abhilash, G.; Dr. Rani Joseph(Cochin University of Science and Technology, August 13, 2015)
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Abstract:
Natural rubber latex, an aqueous colloidal dispersion of polyisoprene is
widely used in production of gloves, catherers, rubber bands etc. The natural
rubber latex content present in products such as gloves causes allergic
problems. Of the different types of allergies reported, latex is known to produce
Type I and Type IV allergies. Type I is called immediate hypersensitivity and
type IV is called delayed hypersensitivity. It has been reported that some of the
proteins present in the latex are mainly responsible for the allergic reactions
type I. Significant reduction in the allergic response (type I) of natural rubber
latex can be achieved by the reduction in its protein content, however out of the
total proteins present in the latex or latex film only a fraction is extractable. The
major techniques employed to reduce protein content of latex include leaching,
autoclaving, chlorination, use of proteolytic enzymes and use of non ionic
surfactants. Sulphur vulcanization of dipped products is responsible for Type
IV allergy. N-nitrosamine, a carcinogenic substance is produced as a result of
sulphur vulcanization. Radiation vulcanization can be used as an alternative for
sulphur vulcanization.
The current research deals with techniques to reduce the allergy
associated with latex products. To reduce the type I allergy, low protein
latex is developed using polyethylene glycol, a non- ionic surfactant. The
present study employs radiation vulcanization to eliminate type IV allergy.
The effect of different cure systems and fillers on the properties of low
protein latex is also investigated as a part of the study.