Fundamentals of Polymer Engineering Part 14 docx

... ! ð13:6:9Þ where E¼molarenergyneededtoovercomeattractiveforces x¼ratioofcriticalvolumeofsolventtothatofpolymersegment ^ VV 0 1 ð0Þ¼occupiedvolumepergramofsolvent ^ VV 0 2 ð0Þ¼occupiedvolumepergramofpolymer ^ VV FH ¼holefreevolumepergramofmixture g;D 0 ¼constant Finally,followingBearman[57],Dudaetal.[58]haveshownthatwhenthe self-diffusioncoefficientofthesolventgreatlyexceedsthatofthepolymer(thi...

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... A., and D. H. Sebastian, Principles of Polymerization Engineering, Wiley, New York, 1983. 4. Kumar, A., and S. K. Gupta, Fundamentals of Polymer Science and Engineering, Tata McGraw-Hill, New ... 3.1. As a matter of fact, one of the practical methods of achieving a PDI of more than 2 is to partially recycle a portion of the product stream, as shown in Figure 3.4 [19–22]....

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... value of De or, equivalently, of the interaction parameter is needed to assure polymer polymer miscibility. Example 9.4: If the 1 g of polymer of Example 9.1 is diss olved in 9 g of a different polymer ... and composed of a series of segments the size of a solvent molecule. The number of segments in each polymer molecule is m, which equals V 2 =V 1 ,the ratio of th...

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... Inc. 6.4RecyclingandDegradationofPolymers285 6.5Conclusion287 Appendix6.1:SolutionofEquationsDescribing IsothermalRadicalPolymerization287 References293 Problems294 7.EmulsionPolymerization299 7.1Introduction299 7.2AqueousEmulsifierSolutions300 7.3SmithandEwartTheoryforStateIIofEmulsion Polymerization304 7.4EstimationoftheTotalNumberofParticles,N t 313 7.5MonomerConcentrationinPolymerParticles...

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... molecular structure of the graft copolymer and the number of grafts formed. In addition, the length of the graft may vary, and the graft copolymer often carries a fair amount of homopolymer. The ‘‘graft-onto’’ ... classification of polymers is based on molecular structure. According to this system, the polymer could be one of the following: 1. Linear-chain polymer 2. Branched-c...

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... Inc. higherthehardnessandmodulus.Anotherfactorthatplaysamajorrolein determiningthefinalpropertyofthepolymeristhechemicalnatureofthe surface.Mineralfillerssuchascalciumcarbonateandtitaniumdioxidepowder oftenhavepolarfunctionalgroups(e.g.,hydroxylgroups)onthesurface.To improvethewettingproperties,theyaresometimestreatedwithachemicalcalled acouplingagent. Couplingagentsarechemicalsthatareusedtotre...

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... application of a vacuum in order to obtain a polymer Reaction Engineering of Step-Growth Polymerization 169 Copyright © 2003 Marcel Dekker, Inc. The total pressure P T is then the sum of partial ... condensation polymerization of two monomers A and B that do not mix. In such cases, the monomers diffuse to the interface and polymerize there. Find the molecular weight of the poly...

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... polymerization. Thus, polymer radicals lie only within these polymer particles. The total number of polymer particles per unit volume of emulsion in the second stage of the emulsion polymerization is ... polymerization in stage II is the growth of polymer particles. If Eqs. (7.6.14a) and (7.6.14b) are divided, we get the average chain length of the polymer within the parti...

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... Inc. alkali.Ifablanksolutionofthebenzylalcoholpluschloroformrequired5mLof thebase,howmanycarboxylendgroupswerecontainedinthepolymersample? Solution:Because30mLof0.105gramequivalentperliterofthebasereacted withthepolymer,theconcentrationofgramequivalentsofendgroupswas ð30Þð10 À6 Þð0:105Þ 0:15 ¼21Â10 À6 equivalentspergram 8.3COLLIGATIVEPROPERTIES Itiseasilyobservedthatdissolvinganonvolatilesolu...

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... Inc. wherekisBoltzmann’sconstant.Inthepresentcase,pðxÞisgivenbyEq.(10.2.9) sothat f¼ÀT d dx À k 2 lnð2npl 2 x ÞÀ kx 2 2nl 2 x  þ dU dx ð10:3:5Þ andcarryingoutthedifferentiation, f¼ kTx nl 2 x þ dU dx ¼ 3kTx nl 2 þ dU dx ð10:3:6Þ Theinternalenergyterminthisequationisrelatedtochangesintheinternal potentialenergyarisingfromthemakingandbreakingofvanderWaalsbonds. Becauserubberselongateveryeasil...

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