What are the reactions involved in the formation of synthetic and natural rubber??
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"Natural" rubber comes from a tree. It is made from the sap of the tree.\n\nSynthetic rubber covers a lot of substances, so you would have to be more specific about the type.
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ref\n\nhttp://www.cem.msu.edu/~reusch/VirtualText/polymers.htm
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I'll talk through it, since I can't draw structures.  Presumably, this is an acid catalyzed process.  The first step is protonation of the oxygen on acetone.  This creates a more electrophilic carbonyl.  One of the hydroxyls of the starting material will attack the carbonyl carbon, generating a hemiacetal.  Protonation of the hydroxyl of this hemiacetal, followed by elimination of water with assistance from the lone pairs on the neighboring oxygen will generate an oxonium ion suited for another nucleophilic attack by the other hydroxyl of the hydrobenzoin.  A final proton transfer will generate the acetal.
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Polymers are substances whose molecules have high molar masses and are composed of a large number of repeating units. There are both naturally occurring and synthetic polymers. Among naturally occurring polymers are proteins, starches, cellulose, and latex. Synthetic polymers are produced commercially on a very large scale and have a wide range of properties and uses. The materials commonly called plastics are all synthetic polymers. \n\n  \n\n             Polymers are formed by chemical reactions in which a large number of molecules called monomers are joined sequentially, forming a chain. In many polymers, only one monomer is used. In others, two or three different monomers may be combined. Polymers are classified by the characteristics of the reactions by which they are formed. If all atoms in the monomers are incorporated into the polymer, the polymer is called an addition polymer. If some of the atoms of the monomers are released into small molecules, such as water, the polymer is called a condensation polymer. Most addition polymers are made from monomers containing a double bond between carbon atoms. Such monomers are called olefins, and most commercial addition polymers are polyolefins. Condensation polymers are made from monomers that have two different groups of atoms which can join together to form, for example, ester or amide links. Polyesters are an important class of commercial polymers, as are polyamides (nylon).
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The reaction may involve the formation free radicals (unstable) as intermediates but reacts with other free radicals and form stable products.
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soap (long alkyl chains with carboxylate salts at the end)\n\nwater\n\nIf the sink has any rubber components, rubber is a polymer of carbon-carbon (as well as other) bonds.
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TO CAUSE THE CHANGE CHEMICAL REACTION
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Compared to the formation of CO2 and H2O, these other products are formed in minute quantities, usually in the part per million level.  \n\n1. Reactions represent what happens under controlled conditions (pure single compound gasoline, pure oxygen).  The burning of gasoline in a car is far from controlled conditions.  The reaction in the car also does not occur to 100% as in the written reaction (formation of CO as a product for example).\n\n2. Another reason is that most of the pollutants form due to impurities in the gasoline.  Again, minor reactants are not shown in the equation since it implies pure starting materials.  These would include sulfur compounds and other organics.  \n\n3. Another reactant not shown for the car reaction is nitrogen.  We normally write "+ O2", but in a car it is "+O2 + N2 + all the other air components".  This is where the nitrogen oxide pollutants arise.\n\nBottom line, unless you are studying them specifically, minor reactants and products are not normally shown.
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How are Rubber Bands made :\n\na) Mixing & Compounding\n\nThe rubber is mixed with various chemicals in required proportions depending on rubber content. This compounded mixture is then strained to ensure that there are no extraneous materials in compounded material.\n\nb) Extrusion\n\nThe compounded rubber is then put into an extrusion machine. This extrudes the rubber into tubing form using specific die heads to achieve a required diameter and wall thickness. The tubing is then cut into lengths and put onto mandrels of the same size / diameter.\n\nc) Curing\n\nThe tubing now on mandrels is put into an autoclave (oven) to ensure tubing reaches it's set form. The tubing is then blown off the mandrels for passing to the cutting area.\n\nd) Cutting\n\nThe tubing is then fed into rotary cutters to cut into designated cut widths of rubber bands.
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CH3CH2CH2CH3 + CL2 -hV--> \nCH3CH2(CL)CHCH3 + HCL ..\n\nwhat are the ways to get the CL at the end of the chain..so that\n\nCH3CH2CH2CH2CL + 2NA + CLCH2CH2CH2CH3\n--->CH3--------CH3\n\nThat's a radical reaction, the chlorination of an alkane with chlorine in UV light. The intermediate is a carbon radical and secondary radicals are more stable than primary. There are also more secondary carbons on this molecule. So probability and reaction kinetics dictates that the primary alkyl halide will be a minor product.\n\nI guess, if this were my synthesis, I'd:\n\n1. Put the glucose in HCl to cleave the anomers it likes to make.\n\n2. Esterify the carboxlic acid with whatever's available (Fisher esterification with MeOH, for example)\n\n3. Reduce the ester with Diisobutyl aluminium hydride (DIBALH)\n\n4. React the aldehyde with 1 equivalent of Ethyl Magnesium Bromide (Grignard)\n\n5. Reduce the hydroxy groups with a Barton-McCombie deoxygenation, although I've never seen it done in a case like this.\n\nThen again:\n\nI'd go to the stockroom and save my research advisor a lot of money. :)
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vulcanised rubber is made by heating the rubber with sulphur.(by Charles Goodyear-1838)\nproperties:even in very high temperatures,it will not loose its elasticity, when the force is taken away it resumes its usual shape, the increased ability to carry weight, doesn't corrode easily.\neg:tyres & tubes, corks, rubber pipes, raincoats, slippers\nhope that helped-cheers!
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U get precipitate of Lead Iodide. The reaction is already mentioned!!!!\n\nPb(NO3)2 (aq) + 2KI (aq) --> 2KNO3 (aq) + PbI2 (s)
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http://en.wikipedia.org/wiki/Condensation_polymerization
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silicone, carbon, nitrogen, sulphur ect. basically eny  elements from grp 4 - grp 7, all group 3 elements r amphoteric( both acid n base) n grp 1 n2 oxides r basic
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reactant(s)\nSynthetic
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Rubber previously came from extraction from actual rubber trees, from the resin within the trees. However, nowadays rubber is manufactured as a by-product of the petroleum industry.
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its cis 1,4 polyisoprene(polymer)\n\nH2C=C(CH2)-CH=CH2