ORGANIC AND PHYSICAL CHEMISTRY OF POLYMERS phần 4 pptx

... prior establishment of a calibra- tion curve from elution volumes of standard samples as a function of their molar mass. Standard samples of polystyrene for polymers soluble in organic solvents or ... means that the mass of the polycondensate where X  was randomly chosen is the sum of the masses of two parts, one standing on the left- and the other on the right-hand side...

Ngày tải lên: 14/08/2014, 10:20

... constant and absolute Organic and Physical Chemistry of Polymers, by Yves Gnanou and Michel Fontanille Copyright  2008 John Wiley & Sons, Inc. 13 4 INTRODUCTION Table 1.1. (continued) 19 74: Development ... eco- nomical point of view—in particular, in the industry of natural and synthetic elastomers. 1,2 or 3 ,4 1 ,4 1 ,4 n n n (see the case of vinyl monomers)...

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... ÷(α 5 −α 3 )  4 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 ... (1 −χ 12 )]andalsoonthemolarmassM 2 of the sample (or X ). Consequently, the excluded volume can be expressed as a function of α from relations (4. 49) and (4...

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... anisotropic particles V v and V h =H v =H h can be written as V v = 16π 4 λ 4 0  α 2 + 4 2 45  V h = H v = H h = 16π 4 λ 4 0 3γ 2 45 148 DETERMINATION OF MOLAR MASSES AND STUDY OF CONFORMATIONS & ... backbone (Figure 5 .44 ). (b) (c) (d) (a) Figure 5 .44 . Representation of liquid crystalline polymers with main-chain (a) and side-chain (b, c) mesogenic group...

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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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... comparison of a pK a of 41 with that of water which is the conjugated acid of metal hydroxides gives an idea of the very high reactivity of the conjugate base. This imposes that monomers are free of ... 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 t...

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... 1 I RO RO O O propagation ZnCl 2 O O I (CH 2 ) 4 (CH 2 ) 4 (CH 2 ) 4 (CH 2 ) 4 O O OR n HI Following the same principle, it is possible to obtain macrotricyclics or eight-shaped bicyclics, and so on. 10 .4. 2. Star Polymers Comb-like polymers ... corresponding mechanisms are often complex but are not different from the basic phenomena described above. 40 4 THERMOMECHANICAL PROP...

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... PROPERTIES OF POLYMERS lna T (T-Tr)°C 40 0 40 0 4 8 12 Figure 12. 14. ‘‘Universal’’ curve giving the variation of a T versus (T −T r )(in ◦ C), according to Williams, Landel and Ferry. elasticity is of ... stress VISCOELASTICITY OF POLYMERS 44 1 (a) (b) s 0 s t f t f e Figure 12 .4. Principle of a creep experiment: (a) Application of constant stress (σ 0 ) between t 0...

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... polymerization of ethylene is more and more utilized because it allows the production of polymers with a better control of the structure than POLYSACCHARIDES AND THEIR DERIVATIVES 501 14. 2.2 .4. Cellulose ... T m =170 ◦ Cand T g =−8 ◦ C. The maximum rate of crystallization is at about 110 ◦ C. The degree of crystallinity lies between 0 .4 and 0.6. VINYL AND RELATED POL...

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... 1 04, 107, 43 4, 46 9. Entanglement: 50, 119, 183, 40 1, 40 3, 41 6, 43 1, 43 4, 43 8, 43 9, 45 7, 45 8, 45 9, 46 9 47 0, 47 3, 47 5, 47 6. Enthalpy of polymerization: 251–253, 2 74, 310, 336. Enthalpy of mixing: ... 1 34, 135, 520, 5 24, 525, 531–532, 579. High pressure (process): 280, 303, 3 04, 344 , 348 , 5 14 515. Hildebrand (solubility parameter): 16. Hookean body...

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