M4 - Non-metals, Rubber & Elastomers Flashcards
elastomers
polymers that are having viscosity as well as elasticity and therefore are known as viscoelasticity
natural rubber
used in the automotive industry and in the manufacture of medical tubes, balloons, adhesives
polyeurethane
used in the textile industry for manufacturing elastic clothing
polybutadiene
used for providing wear resistance in wheels of vehicles
silicone
used in the manufacture of medical prostheses, lubricants as they have an excellent chemical and thermal resistance
neoprene
used in the manufacture of wet-suits and in industrial belts
types of elastomers
saturated elastomers
unsaturated elastomers
saturated elastomers
- Good stability against oxygen, radiation, heat, and ozone
- Reactivity is limited to certain circumstances and condition
unsaturated elastomers
- Cured with Sulphur vulcanization process
- Ex. Butyl rubber and natural polyisoprene
temperature
specific working temperature of elastomers vary depending on the factors like media compatibility, seal design, and the dynamic and static operation
low-temperature flexibililty
The rate of recovery of elastomeric material can be studied by subjecting the material to low-temperature retraction
hardness
the measurement of the material’s resistance towards the deforming force for a defined length of time
ageing
tells the behavior of a material when exposed to heat
color
to differentiate between the compound grades based on their usage
elongation at break
for testing the moment of rupture when the material is under tensile stress
production processes of elastomers (9)
mixing textile treatment calandering spreading extrusion mold curing rubber-metal bonding vulcanization latex processes
mixing
uncured compound is manufactured in order to be used for further processing into a rubber product
textile treatment
Reinforcing material has to be treated to obtain dimension stabilized products with good bonding between rubber and the reinforcing material
calandering
to make flat sheeting, rubber coated fabrics as uncured products or as semi product parts
spreading
for manufacturing thin rubber coated fabrics
extrusion
for manufacturing long length products which can be cured to final products or be used as parts in confectioned rubber products
mold curing
for molding rubber (compression, transfer and injection molding) and for post-processing of cured products
rubber-metal bonding
the metal has to be degreased and treated with bonding agents before molding or autoclave curing
(for good bonding between rubber and metal)
vulcanization
All different curing methods used to cure products shaped by the previous processes
latex processing
used for manufacturing of products from liquid rubber latex
in contrast to previous methods, which used dry rubber
