Chain molecular weight

Starch is a mixture of glucose polymers, some of which are water-soluble. This soluble portion consists of comparatively short chains (molecular weight 4000). The portion of low solubility involves much longer chains and the polymer chain is branched. 

With regard to elastomers of controlled structure, those having unusual distributions of network chain lengths have been of particular interest [88,89]. The most novel elastomer of this type consists of a binary combination of unusually short network chains (molecular weights of a few hundred) and the much longer chains typically associated with elastomeric behavior (molecular weights of ten or twenty thousand). Such a network is sketched in Figure 6. 

It should be pointed out that there are three requirements for obtaining these improvements. The first is that the ratio Ms/Ml of molecular weights of the short (Ms) and long chains (Ml) be very small (i.e., that their molecular weights be very different). The second is that the short chains be as short as possible for example, a network having network chain molecular weights of 200 and 20,000 g/mol... 

Table 9.2 Characterization results for two series of arborescent polystyrenes with different side chain molecular weights (adapted from ref. 4)...

The basic structure of an immunoglobulin molecule, such as the major serum antibody IgG, consists of four polypeptide chains two identical light chains (molecular weight around 25 000 daltons) and two identical heavy chains (with a molecular weight around 50 000 daltons), cross-linked by disulfide bonds to form Y-shaped molecules with two flexible arms (Fig. 11.2). The binding sites are located on the arms and vary from one molecule to another (variable region) [22b]. 

Polypeptide Chain Molecular Weight Determination by Gel Permeation Studies on Agarose Columns in 6M Guanidinium Chloride... 

K.G. Mann and W.W. Fish, Protein polypeptide chain molecular weights by gel chromatography in guanidinium chloride, in C.H.W. Hirs and S.N. Timasheff (Eds.), Methods in Enzymology, Vol. XXVI, Enzyme Structure, Part C, Academic Press, New York, 1972, pp. 28-42. 

Figure 15.8 2H NMR spectra obtained in a randomly crosslinked, deuterated PB network. Precursor chain molecular weight 115700 g.mol"1, 1.2% crosslink agent, the average molecular weight between junctions is 27400 g.mol 1 (as determined by swelling experiments) or 11600 g.mol"1 (elastic measurements). The smooth curves are fits with a most probable distribution of chain lengths with number average molecular weight Mc = 11600 and with non-Gaussian chain statistics...

UQ may also be reduced by complex II (succinate ubiquinone oxido-reductase, succinate dehydrogenase), which contains four polypeptide chains, molecular weights 70,000, 27,000, 15,500, and 13,500. The first two constitute bona fide succinate dehydrogenase, a Krebs cycle enzyme catalyzing reaction... 

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