Sunil,K Narayanankutty(John Wiley & Sons. Inc., June 21, 2001)
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Abstract:
The effect of diphenylmethane diisocyanate
(MDI) -polyethyleneglycol (PEG) resin on the cure characteristics and mechanical
properties of nitrile rubber/whole tyre eclaim-short nylon fiber
composite-was studied. At a constant loading of 5 phr, the resin composition
was varied. The minimum torque .,id (maximum - minimum) torque increased
with isocyanate concentration. Scorch time and cure time showed a reduction on
introduction of bonding agent. Properties like tensile strength, tear strength, and
abrasion resistance increased with increase in MDI/PEG ratio, and these
properties are higher in the longitudinal direction of fiber orientation.
Compression set increased with isocyanate concentration and the resilience
remain unchanged.
Blends of nitrile rubber and reclaimed rubber containing different levels of a
coupling agent, Si 69 (bis(3- triethoxysilyl propyl)(tetrasulphide) were prepared
and the cure characteristic's and mechanical properties were studied. Optimum
loading of Si-69 was found to be a function of blend ratio. 3 phi- of Si 69 in a
70:30. Blend was found to be the optimum combination with respect to the
mechanical properties. The rate and state of cure were also affected bv the
conp/ing agent. Tensile strength, tear strength and abrasion resistance were
improved in the presence of coupling agent. While the state of cure improved,
the cure rate and scorch time decreased with increasing silane content. Ageing
studies showed that the blends containing the coupling agent were inferior to
the unmodified blends.
ABSTRACT: Linseed oil is used in the dual roles of the plasticizer and the fatty
acid component of the activator in nitrile rubber vulcanizates. The study shows
that the substitution can substantially improve the mechanical properties in
addition to other advantages such as increased cure rate, reduced leachability
and reduced compound cost.
Zinc salts of ethyl, isopropyl, and butyl xanthates are prepared
in the laboratory, and the effect of these xanthates with zinc diethyl
dithiocarbamate (ZDC) on the vulcanization of HAF-filled nitrile butadiene
rubber (NBR) compounds has been studied at different temperatures. The cure
times of these compounds have been compared with that of NBR compounds
containing TMTD/MBTS. The rubber compounds with the three xanthate
accelerators and ZDC are cured at various temperatures from 60 to 150°C.
The sheets are molded and properties such as tensile strength, tear strength,
cross-link density, elongation at break, compression set, abrasion resistance,
flex resistance, etc. have been evaluated. The properties show that zinc salt
of the xanthate/ZDC accelerator system has a positive synergistic effect on the
cure rate and mechanical properties of NBR compounds.
Anantharaman, M R; Soloman, M A; Joy, P A; Philip, Kurian(CSIR, July 5, 2005)
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Abstract:
Fine particles of barium ferrite (BaFe12O19) belonging to the M-type hexagonal ferrites were prepared by the
conventional ceramic techniques. They were incorporated into a nitrile rubber matrix according to a specific recipe for
various loadings to produce rubber ferrite composites (RFC). The percolation threshold is not reached for a maximum
loading of 130 phr (parts per hundred rubber). Here in this paper, the magnetic properties and processability of the nitrile
rubber based RFCs containing barium ferrite (BaF) and HAF carbon black is reported. The magnetic properties of the
ceramic ferrite and these rubber ferrite composites were evaluated and it was found that the coercivity values of RFCs were
less than that of the ceramic BaF, but remained constant with the loading of both the ferrite filler and carbon black.
However, other properties like saturation magnetization and magnetic remanence increased with the loading of ferrite filler.
Description:
Indian Journal of Chemical Technology
Vol. 12, September 2005, pp. 582-587
Zinc salts of ethyl, isopropyl, and butyl xanthates
were prepared in the laboratory. The effect of these
xanthates in combination with zinc diethyldithiocarbamate
(ZDC) on the vulcanization of silica-filled NBR compounds
has been studied at different temperatures. The cure times
of these compounds were compared with that of NBR compounds
containing tetramethylthiuram disulphide/dibenzthiazyl
disulphide. The rubber compounds with the xanthates
and ZDC were cured at various temperatures from
60 to 150°C. The sheets were molded and properties such as tensile strength, tear strength, crosslink density, elongation
at break, compression set, abrasion resistance, flex resistance,
heat buildup, etc. were evaluated. The properties
showed that zinc salt of xanthate/ZDC combination has a
positive synergistic effect on the cure rate and mechanical
properties of NBR compounds.
Rani, Joseph(OPA (Overseas Publishers Association), May 28, 1995)
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Abstract:
Amine Terminated Liquid Natural Rubber (ATNR) was used as a plasticiser in filled NR and NBR
compounds replacing oil/DOP. The scorch time and cure time were found to be lowered when ATNR
was used as the plasticiser. ATNR was found to improve the mechanical properties like tensile strength,
tear strength and modulus of the vulcanizates . The ageing resistance of the vulcanizates containing ATNR
was superior compared to the vulcanizates containing oil/DOP.