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Animated science topic " Rubber " : It is derived comes from the sap of the Para rubber tree, Hevea brasiliensis. It is a colloid. Natural rubber is chemically poly-cis-isoprene formed from monomer isoprene.Vulcanization is a process for hardening rubber. Rubber is heated with Sulphur or Sulphur compounds. This animated chemistry topic gives in-depth information about Rubber and is very useful for schools and industry.
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Rubber and its chemistry
Content : Educational
science software
Type : Animation
Duration : 11 minutes
Topics Covered :
- What is rubber?
- How is rubber prepared?
- What are properties of rubber?
- What is chemical composition of rubber?
- What is vulcanization of rubber?
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Vulcanization of rubber
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Process of making rubber from sap
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Chemically rubber is poly-cis-isoprene
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Content of the science animation
: Natural rubber is chemically poly-cis-isoprene which
is formed from the monomer isoprene. It comes from the sap
of the Para rubber tree, Hevea brasiliensis. Trees are tapped
by making a spiral cut through the bark. The sap is called
latex. It is a white milky liquid. It is a suspension of
tiny particles of rubber in water. These particles can be
separated when acid is added to it and solid rubber is obtained.
Vulcanizing is a process for hardening rubber. The rubber
obtained from the tree is sticky and soft. In vulcanization
process rubber is heated with Sulphur or Sulphur compounds
at a definite temperature for a definite time.
Vulcanizing causes the long molecules to form chemical bonds
that join them side-to-side. The sulfur chains help to align
the polymer chains, so the material does not undergo a permanent
change when stretched but spring back to its original shape
and size when the stress is removed
This treatment converts the soft, sticky mass of rubber
into a hard, tough substance. This process is used in the
manufacturing of tires of vehicles.
All about it inside the animation.
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Q1: |
I just sent the $12.00 via paypal. How do I see the video? |
Ben C. Brodhead |
1/2/2013 |
Ans: |
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Q2: |
what are the spedification of natural rubber that are being used in making tire |
grace apostol |
17/9/2007 |
Ans: |
Rubber for tyres falls under HS code 4001.21 and is graded as RSS1, RSS2, RSS3, RSS4, RSS5 depending on quality, as per international Standard of Quality and Packing for Natural Rubber Grade, here RSS stands for Ribbed Smoked Sheet and HS expands to Harmonized Commodity Description and Coding System. A rubber strip fresh out of mill is sliced into sheets and is dried by placing it in a smoke house. Smoking dries it, impregnates creosotic substances that serve as anti-oxidants and antiseptics. |
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Q3: |
chemical composition of rubber in producing shoes and rubber type |
Hai Van |
29/6/2006 |
Ans: |
Nowadays natural and synthetic rubbers are used mainly for soles and heels of footwear, these are emulsion styrene-butadiene-rubber (ESBR), chloroprene-rubber, isoprene-rubber, butadiene-rubber, nitrile-rubber, and natural rubber(latex). There is a lot of variation in composition of each, a typical ESBR composition for cold process can be (Parts by weight) Styrene 25, Butadiene 75, Water 180, Emulsifier (FA,RA, MA) 5, Dodecyl mercaptan 0.2, Cumene hydroperoxide 0.17, FeSO4 0.017, EDTA 0.06 |
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