Two questions of Polymerisation of Alkenes?
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Sharp melting temperatures are a characteristics of those substances which have a definite fixed structure, with always the same number of atoms and bonds throughout. This description would includes almost all substances we know because all have a fixed molecular mass; but this doesn't apply to polymers, because the polymers chains produced in the industry are of varying lengths - they would have the same characteristic repeating unit throughout the chain; but their chain lenghts can vary from a few hundred single units (joined together) to tens of thousands of them. A polymer with a short chain length will have less surface area - therefore less contact - and consequently less number of weak vanderwaal forces among them. A less quantity of these forces in a polymer would require less energy to be broken and hence have a less melting temperature (and vice versa). So polypropene would "soften over a range of temperatures" until all the long and short- chained polymer structures melt out. \n\nAs for the empirical formula, yes I guess you're right - though it's better to write it as (C3H6)n, where 'n' denotes many repeating units. I thought it would be CH2 if we simplify C3H6 further, but then CH2 would be the empirical formula for propene. (as in any homologous series)
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http://en.wikipedia.org/wiki/Condensation_polymerization
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I attached a thermal method for styrene\n\nThe photoinitiation is a bit more complicated and under research.  No known monomer can photopolymerize itself. It works by using photons to break apart special initiators/catalysts that form cations, anions or free radicals needed for polymerization.  While there laboratory models about photoinitiation, you would need an actual lab to control the reaction, because no kitchen or work bench will do. Good luck.
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It's a carbon-hydrogen chain. \nIt is used in organic reactions.
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There are all kinds of different materials lumped under the generic heading of "plastics".  The variations run into hundreds, perhaps even thousands of compounds!\n\nFor example, there's nylon.  The most familiar form, nylon 66, is a copolymer of adipic acid or adipoyl chloride and hexamethylene diamine.  But I can substitue various hydrocarbon chains in those two components to make nylon 55, nylon 65, nylon 48, nylon 83, etc.\n\nThen there are the families of polyaramid polymers, and polyester polymers, and polycarbonates, and . . . .\n\nNobody will ever be able to give you an exhaustive list here.  Try looking up some books on polymer chemistry at your library.
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Grignard Synthesis of Benzoic Acid\n\n\nPreparation:  McMurry, sections 10.8 and 20.6.\n\nConversion of an organic halide into a Grignard reagent completely transforms the reactive character of the organic compound. Carbon bears partial positive charge when bonded to halogen but partial negative charge when the carbon is bonded to magnesium. The Grignard reagent is a very reactive nucleophile and base. \n\nIn this experiment you will make the Grignard reagent phenyl magnesium bromide; this reagent will then be treated with carbon dioxide to form benzoic acid. The sequence (Equation I) is explained in McMurry Sect 20.6.\n\n\nAs in any work, this experiment may not succeed the first time; be prepared to repeat it from the beginning. On the second try, you should be able to work much more efficiently and with more understanding. \n\n\nProcedure: Obtain a 150 mm piece of magnesium ribbon. Hold one end with forceps and with the other hand remove the residue on the ribbon by scraping it with a spatula, scissors or pliers to obtain a shiny surface. Cut at least 0.12 g of the shiny ribbon into 2-3 mm pieces (do not handle the pieces) and place on a folded piece of paper to obtain the mass on the balance. Transfer the magnesium pieces to the 5 mL conical vial, add the dry spin vane, add one small crystal of iodine and add 300 µL (0.3 mL) of anhydrous ether. Be prepared to add more ether as necessary to maintain the liquid level at a minimum of 300 µL.\n\nAssemble the rest of the apparatus as in Mayo, et al., Fig 3.24. Clamp the apparatus firmly to a stand.\n\nIn the hood, prepare a solution of 510 µL of bromobenzene in 700 µL of anhydrous ether in the 3 mL vial using the delivery pipettes provided. Cap this vial with a polyethylene top. \n\n(*Note:  Be certain the dry ice is ready before you initiate the reaction below.)\n\nDraw half of the bromobenzene solution into the syringe and insert the needle through the polyethylene cap in the Claisen head as in the figure. While stirring the mixture below, add 6-8 drops of the bromobenzene solution. Evidence of reaction is the formation of tiny bubbles. When the reaction has started, add the remainder of the bromobenzene solution slowly over 3-5 min. The temperature should be maintained at about 40 oC to allow gentle refluxing (Mayo, et al., p. 29) of the ether. To the 3 mL vial add an extra 300 µL of ether, then transfer this to the reaction via the syringe. Adjust the total volume to 3 mL with the addition of more anhydrous ether. Reflux the mixture for 10 minutes, then allow the gray-brown solution of the Grignard reagent to cool to room temperature. What do you observe?\n\nThe Dry Ice (at least 1.0 g) is added in small chunks to the Grignard solution. Note the reaction as this is added. To convert the C6H5C(=O)-OMgBr, to benzoic acid (last step, Equation I), use a pipet to VERY SLOWLY add 1 mL of 6 N HCl and again observe the result. Test the aqueous layer with pH paper; it should be acidic. Remove the ether by gently heating the vial for 5 minutes on the steam bath. Cap the vial, mark it and set it in your drawer until the next laboratory period. \n\nPreparation for the 2nd laboratory period:  The benzoic acid has been synthesized, but it must be purified. Water soluble magnesium salts are removed by extracting away the water layer; but, a number of organic side products remain with the benzoic acid.  These are side products of the Grignard reaction; small amounts of benzene are formed (Equation II), unreacted bromobenzene remains, and biphenyl, H5C6-C6H5, is formed from the reaction (Equation III). \n\nThe benzoic acid can be isolated from this mixture by taking advantage of its property as an acid. Only it can dissolve in aqueous NaOH (Equation IV) while the side products remain in the ether. After the ether-soluble side products have been removed, strong acid is again added to reverse this reaction in order to restore the benzoic acid.\n\nRecrystallization of the crude product in
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Chemistry relating to Carbon derivatives.
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I'll go out on a limb and suppose that you need some very simple projects that can demonstrate polymer properties to the layperson.\n\nPhysics:  \n\nIf you take a rubber band, an elastomer, suspend a weight from it, and gently heat the rubber band with something like a hair drier, you can demonstrate that polymer chains prefer to adopt a random coil configuration rather than a straight, linear configuration. (I'll leave out the basic thermodynamic details so you can delve deeper into the subject.)\n\n\nChemistry:\n\nTo demonstrate the differences in size between polymers and small molecules, look up the size of a single water molecule and then get a piece of foam rubber.  The water molecule's size is on the order of Angstroms, while the foam rubber is essentially one gigantic molecule.\n\nIf you have access to sebacoyl chloride and hexamethylene diamine, you can make Nylon-6 by using equal parts of both reactants.  The polymer forms at the interface of the two liquids, and you can use tweezers to pull the polymer out of the reaction vessel.  NOTE:  Proper safety precautions MUST be followed as both chemicals are irritants. \n\nI've left out sources and a lot of other details so you can research the physics/chemistry of the examples given here.
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Hey buddy  you may take  a  look at this  site which offers  this  kinda  services and explains everything slightly  good:http://www.e1.greatlakes.com/corp/prodserv/jsp/optical_monomers.jsp\n\nThis also:http://industrial-adhesives.globalspec.com/Industrial-Directory/monomer_MSDS_styrene\n\nand  about  acrylic glass:http://en.wikipedia.org/wiki/Polymethyl_methacrylate
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It's a monomer derive from petroleum , exactly how I am not sure  since I only do plastics.\n\nThe monomer is receive as is for polymerising to make   ,  pe , polyethylene.  Which makes the our plastic bags and some hoses (aquarium hoses).\n\nOn the re-cycle logo you can see "pe" , because today we have to declare. \n\nWhen the primodial bog sinks and plants turn to gas , petroluem and coal , ethylene is somewhere in there.\n\n** therefore the energy is solar at source , origin.
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The nobel prize this year was presented to Yves Chauvin  Robert H. Grubbs and Richard R. Schrock for their work on Alkene Metathesis.\n\nThe Nobel prize for work on Fullerenes was presented in 1996 to Harry Kroto, so I think although this is a developing field it is quite old.\n\nThere is always a wealth of information being published for new chemistries every week.  There are hundreds of journals dedicated to providing new results, new reactions, new mechanisms etc.  I suppose really you are looking for those which have had the greatest impact on society, rather than within the chemical community.\n\nWithin the chemical community I would say with confidence the development of combinatorial and parallel synthesis using solid-support or solid-supported reagents has had an unparalleled impact on the speed of pharmaceutical research and the development of new drugs.\n\nWhere society might notice the use of chemistry - perhaps in plasma screens, high definition televisions.  \n\nThese are just my opinions and I am sure there are many other applications as noteworthy that should be mentioned.
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There are too many challenges in this molecule to come up with a synthesis in a few minutes.....1 chiral centre, 2 quartenary carbon centres next to each other, and geometrically specific double bonds.  However many syntheses have been completed.  The references below will direct you to published syntheses of analogues.  The first two are probably the most useful.\n\nTetrahedron, 1992, 8229-8238\nTetrahedron Letters, 1972, 2521-2524\nTetrahedron Letters, 1999, 6347-6351\nTetrahedron Letters, 1997, 1797-1800\nPhytochemistry, 1996, 23-28\nBioorganic and Medicinal Chemistry Letters, 1995, 275-278\nTetrahedron Letters, 1989, 1741-1744\nTetrahedron Letters, 1988, 5339-5342\n\nyou can access the journals through www.sciencedirect.com, but you may need to pay for them if your institution doesn't have access.\n\nhttp://cbr-rbc.nrc-cnrc.gc.ca/abscisicacid/\n\nAlso try the link above - gives you some more information.\n\nHope this helps.
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i don't know exactly how the film is made. but the polythene is made up of monomers called ethene. Ethene is an alkene - notice the 'ene' on the end. Ethene has come from a process of 'cracking'. Before cracking, ethene was ethane - and guess what these are called- alkanes - notice the 'ane'. Alkanes make up crude oil, which we fractionally distill to get fuels such as petrol (for cars) and kerosine( aeroplane fuel)  \nAll these monomers (ethene) will join together to make a polymer - which in this case is polythene - in theory it should be called polyethene, not polythene. This process is called polymersiation. \n\nthis is it in basic form\n\ncrude oil ---> fractionally distilled (burn off fuels at certain temperatures) ----> get alkanes (which have a single carbon bond)-->process of cracking --> get an alkene (which have a double carbon bond - making it more reactive than an alkane) -->example - get ethene, which is a monomer ---> this monomer comes together with other monomers to make a polymer----> this process is polymerisation ----> the ethene monomers will come together to form polythene\n\nThere are other examples - such as the alkane - propane - notice 'ane' again. Once propane is cracked, it will form into an alkene called propene - notice 'ene' - the monomers are propene. So loads of propene monomers will come together (polymerisation) and form polyPROPene , not polyTHEne
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1) H3COCH3 (or C2H6O) + 3O2 (g) --> 2CO2 (g) + 3H2O (g)\n2) HNO2 (aq) + NaOH (aq) <--> NaNO2 (aq) + H2O (l)\n3) 2K+ + Cr2O7(2-) + Fe(NO3)2 + 2H+ <--> CrO4(-) + Fe3+ + 2K+ + 2NO3(-) \n4) Na3PO4 + NH4NO3 = No reaction, all soluble salts.\n5) 2HCl (aq) + Na2S (s) --> 2NaCl (aq) + H2S (g)
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From which perspective?  Reactions or Transport or both?\n\nLike, if you want to do reactions, you can give a rate law for absorption and reaction on a catalyst.  Solve for the PBR size necessary to give X % conversion of the reactants.\n\nFrom a mass transport standpoint, perhaps look at the mass flux of reactant to a catalyst surface?
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a) 2C2H6 + 7O2  --> 4CO2 + 6H2O\n\nb) C6H12 + 9O2  --> 6CO2 + 6H2O\n\nc) C5H12 + 8O2  --> 5CO2 + 6H2O\n\nYou must apply Markovnikov rule for the next addition reactions:\n\na) CH2=CHCH2CH3 + HCl  --> CH3CH(Cl)CH2CH3\n\nb) CH2=C(CH3)CH3 + HBr  --> CH3-CBr(CH3)CH3
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(a)2-Chloro-2-methylpentane\n(b)2,3-dihydroxy-2-methylpentane\n(c)Probably 1-Ethyl-2-methylpropanesulfonic acid also can be called 2-(i-propyl)propane sulfonic acid\n(d)2,3-Epoxy-2-methylpentane (you form an epoxide of the alkene)\n(e) You'll probably get a mixture of 2,3-dibromo-2-methylpentane and 3-bromo-2-methyl-pentan-2-ol\n(f) You'll get two products.  Isopropanol and n-propanol.