Polymer mer

Carraher, C. E. Sheats, J. Pittman, C, U. "Metallo-Organic Polymers" MER Moscow, Russia, 1981. 

Polymer Mer Group Relative Molar Cohesion per 5 A Length... 

A somewhat better value of can be estimated from the use of group contributions [21] Table 2-7 lists such contributions for some typical polymer mer constituents. 

Finally, the question arises as to the effect of the polymer itself on diffiisivity for a given gas. Figure 5-10, which plots the diffiisivity vs polymer mer weight for the same gas, shows this effect. As evident from Fig. 5-10, the diffiisivity decreases with increasing mer weight. 

Monomer. A simple molecule which is capable of reacting with like or unlike molecules to form a polymer the smallest repeating structure of a polymer (mers) for addition polymers, this represents the original unpolymerized compound. 

Polymerization processes yielding polymers, whose mers are constitutionally identical to the reacting monomers are now classified as addition polymerizations. Thus styrene can be converted, by addition polymerization, to polystyrene ... 

Here the empirical compositions of polymer and reacting monomers are dilTerent and the structural unit (mer) has no constitutional identity with the monomer components. 

By controlhng the relative amounts of, for example, glycerol and phthahc anhydride and the experimental conditions of the reaction, various pol5 mers of different properties are obtained. Under mild conditions (ca. 150°) only the primary alcohol groups are esterified and the secondary alcohol group remains free. The structural unit of the resulting linear polymer is ... 

One of the mam uses of the linear a olefins prepared by oligomerization of ethylene is in the preparation of linear low density polyethylene Linear low density polyethylene is a copoly mer produced when ethylene is polymerized in the presence of a linear a olefin such as 1 decene [H2C=CH(CH2)7CH3] 1 Decene replaces ethylene at random points in the growing polymer chain Can you deduce how the structure of linear low density polyethylene differs from a linear chain of CH2 units ... 

We begin by recognizing that the weight fraction w of n-mers in the polymer mixture at any value of p equals the ratio of the mass of n-mer in the mixture divided by the mass of the total mixture. The former is given by the product uN Mq, where Mq is the molecular weight of the repeat unit the latter is given by NqMq. Therefore we write... 

Dividing both sides of Eq. (6.58) by [M-], the total radical concentration, gives the number fraction of n-mer radicals in the total radical population. This ratio is the same as the number of n-mers in the sample containing a total of N (no subscript) polymer molecules ... 

This expression gives the number fraction or mole fraction of n-mers in the polymer and is thus equivalent to Eq. (5.25) for step-growth polymerization. 

In Chap. 5 all molecules—whether monomer or n-mers of any n—carry functional groups hence the fraction described by Eq. (5.24) applies to the entire reaction mixture. Equation (6.67), by contrast, applies only to the radical population. Since the radicals eventually end up as polymers, the equation also describes the polymer produced. Unreacted monomer is specifically excluded, however. 

Since the total number of polymer chains is proportional to [B"]o, the number of n-mers in a population of N polymer molecules is given b>... 

Figure 6.11 Comparison of the number distribution of n-mers for polymers prepared from anionic and free-radical active centers, both with f = 50.

Next we consider the fraction of n-mer in a specific phase. The volume of n-mer in each of the phases is given by pVp and q q > therefore the fraction of polymer in the two phases is... 

Figure 8.5 Theoretical plots of weight fraction n-mers versus n for unfractionated polymer (A), the dilute phase (B), and the concentrated phase (C) (drawn with R = 10 ). (Adapted from Ref. 1.)...

Special symposia, outside these three series of symposia, include a special and unique Moissan symposium, held in 1986 in Pans at the hundred year anniversary of the preparation of elemental fluorine, a symposium on Synthetic Fluorine Chemistry held m 1990 in I os Angeles, and a symposium on Fluorinated Mono mers and Polymers held in 1993 in Prague, Czechoslovakia... 

Grafting provides a convenient means for modifying the properties of numerous polymers. It is often required that a polymer possess a number of properties. Such diverse properties may not be easily achieved by the synthesis of homopolymers alone but can be achieved through the formation of copolymers or even terpoly-mers. The formation of graft copolymer with sufficiently long polymeric sequences of diverse chemical composition opens the way to afford speciality polymeric materials. 

L. A. Utracki et al.. Polymer Alloys, Blends and lono-mers An overview in Multiphase Polymers Blends and lonomers (L. A. Utracki and R. A. Weiss, cds.), ACS Symposium Series No. 395, 1-35 (1989). 

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