ORGANIC AND PHYSICAL CHEMISTRY OF POLYMERS phần 6 doc

... r 1 and r 2 are the ionic radius of cation and anion, respectively, and e is the electron charge. This relation shows that by increasing the apparent ionic radius of the cation and that of the ... radius of the lithium ion; the attack of carbonyl groups by ion pairs can thus be thwarted, the probability of termination reduced, and the control of polymerization improved...

Ngày tải lên: 14/08/2014, 10:20

... transitions and relaxations of polymers, their mechanical properties and their rheology. These thirteen chapters are rounded off by monographs (chapters XIV to XVI) of natural polymers and of some ... and degradation of covalent bonds and formation of small molecules. The measurement of E co requires the use of indirect methods such as the comparison of swelling o...

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... REACTIVITY AND CHEMICAL MODIFICATION OF POLYMERS degradation by depolymerization m t M n t degradation by random chain breaking m t t M n Figure 9.2. Variations of both molar mass and mass of polymer ... use of techniques of high sensitivity and precision such as mass spectrometry (MALDI-TOF) is helpful with respect to the identification of these functional groups. 10.3....

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... ÷(α 5 −α 3 )  4πs 2  0 3  3/2 F(Y) (4 .63 ) with Y = 2(α 2 −1) (4 .64 ) The expressions (4 .62 ) and (4.53) show that the radius of gyration of a chain subjected to the phenomenon of excluded volume is proportional ... u after n steps is the product of the probability of having a sequence of n + positive moves and n − negative moves, each one of probability 1/2 times the...

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... the mass of the solute, V 1 and V 2 are the volumes occupied by the solvent and the solute, N 1 and N 2 are the number of molecules of solvent and solute, and M 2 is the molar mass of the solute. One ... characteristic textures of the various mesophases; he can also make use of differential scanning calorimetry and of X-ray diffraction. 1 56 DETERMINATION OF MOLAR...

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... polymer including x points of branching of functionality f and p grafts, we obtain g = 6p 2 +(f − 1)x(x 2 −1) 6p(p +1)(p +2) (6. 64) with p =(f −1)x. 6. 4.4. Techniques of Measurement It is imperative ... X and vice versa, p X and p Y are related by the equation 4X 4 p X = 2N Y p Y 2 06 DETERMINATION OF MOLAR MASSES AND STUDY OF CONFORMATIONS & MORPHOLOGIES Table 6....

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... char- acter and afford chains and architectures of controlled size and structure are in great demand. Among the specific characteristics, one can mention a low dispersity of chains. Such a narrowing of ... Probability (P tr ) of formation of i, h,ands triads, according to Bernouillian statistics. In Figure 8.1 are plotted the variations of the probabilities of existence of...

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... units up to the overall movement of the chain, through the use of a suitable analytical technique. Organic and Physical Chemistry of Polymers, by Yves Gnanou and Michel Fontanille Copyright  ... FORMULATION, AND POLYMER PROCESSING TECHNIQUES two models, that of Rouse and that of reptation, thus differ by their description of both the diffusion and the viscosity...

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... degree of crystallinity lies between 0.4 and 0 .6. VINYL AND RELATED POLYMERS 535 for the formation of small-size crystallites (“discs” of ∼1 nm thickness and ∼4nm diameter), which are zones of strong ... bases (one internal and one external) to attain rates of mm triads close to 99% and activities (see definition in Section 8.8.2) of several hundreds of grams of P...

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... 4 76. Enthalpy of polymerization: 251–253, 274, 310, 3 36. Enthalpy of mixing: 50, 55–57, 62 63 , 66 , 78, 82, 83. Entropy of mixing: 50–54, 57, 62 , 63 , 65 68 , 78, 82–84, 86, 149, 1 96. EPDM (elastomer): ... 395–398. Ideal solutions: 50, 54, 55, 66 . Initiation, Initiators (of polymerizations): 249, 250, 2 56 258, 260 , 262 , 263 , 265 , 266 , 268 –274, 278–280, 282–2 86,...

Ngày tải lên: 14/08/2014, 10:20