Properties of cross-linked

This material finds a limited application in films and coatings which require good abrasion and flexing resistance. Some typical properties of cross-linked and uncross-linked polymers are given in Table 18.9. 

FIGURE 9.18 Elastic properties of cross-linked recombinant resilin. (a) A single force-extension curve recorded for a sample of cross-linked recombinant resilin (approach curve solid, retract curve dotted). 

Since the excellent work of Moore and Watson (6, who cross-linked natural rubber with t-butylperoxide, most workers have assumed that physical cross-links contribute to the equilibrium elastic properties of cross-linked elastomers. This idea seems to be fully confirmed in work by Graessley and co-workers who used the Langley method on radiation cross-linked polybutadiene (.7) and ethylene-propylene copolymer (8) to study trapped entanglements. Two-network results on 1,2-polybutadiene (9.10) also indicate that the equilibrium elastic contribution from chain entangling at high degrees of cross-linking is quantitatively equal to the pseudoequilibrium rubber plateau modulus (1 1.) of the uncross-linked polymer. 

Kinetics of Intramolecular Cross-Linking and Conformational Properties of Cross-Linked Chains... 

The method of mathematical simulation has many advantages, and is very close to the physical experiment. However the further development of this approach /a consideration of volume effects, reversible reactions and so onj can be rather difficult because it will reau.ire too much computer time, therefore it is expedient to search some simple analytical or semianalytical approximate approaches to the calculation of cross-linking kinetics and conformational properties of cross-linked macromolecules. The results obtained bv the Fonte Carlo calculation can serve as criteria of the accuracy of such approximation. 

Thus the approach described can be apolied to the description of the kinetics of intramolecular cross-linking and the conformational properties of cross-linked products. 

The merging of the properties of cross-linked polystyrene and soluble PEG is achieved in so called tentagels. Here, the hydrophobic properties of cross-linked... 

Variation of Properties of Cross-Linked Methacrylate Resists with Curing Conditions... 

Liu, H., Ramsden, L., Corke, H. (1999b). Physical properties of cross-linked and acetylated normal and waxy rice starch. Starch, 51,249-252. 

Zheng, G. H., Han, H. L., Bhatty, R. S. (1999). Functional properties of cross-linked and hydroxypropylation waxy hull-less barley starches. Cereal Chem., 76,182-188. 

Mancke.R.G., Dickie,R.A., Ferry,J.D. Dynamic mechanical properties of cross-linked rubbers. V. An approximate analysis of the modulus contributions of trapped and untrapped entanglements. J. Polymer Sci., Part A-2 6,1783-1789 (1968). 

Chemistry and Properties of Cross-Linked Polymers Labana, S.S., Ed. Academic Press New York, 1977. 

Dybowski CR, Vaughan RW (1977) in Labana SS (ed) Chemistry and properties of cross-linked polymers, Academic, New York, pp. 547-558... 

Lee, J., Macosko, C. W., and Urry, D. W. (2001a). Mechanical properties of cross-linked synthetic elastomeric polypentapeptides. Macromolecules 34, 5968-5974. 

All cationically polymerizable monomers can be potentially used in this process however, the main study has been focused so far on the most reactive oxirane and vinyl ethers [4], Alkoxysilane derivatives - the most common acid-sensitive monomers for the synthesis of siloxane materials through the use of sol-gel methods - were not used extensively. Only a few examples of their application in photo-activated cross-linking can be noted, mainly in co-reaction with oxirane sites [5]. Typically, alkoxysilanes are subjected to an acid- or base-catalyzed process involving hydrolysis of an =SiOR group and then condensation of the formed silanol with another molecule bearing an =SiOH or =SiOR function to give a siloxane linkage [6]. It was of interest to combine the properties of cross-linked silicone materials with the ones provided by sterically overloaded... 

Sundararaghavan HG, Metter RB, Burdick JA (2010) Electrospun fibrous scaffolds with multiscale and photopattemed porosity. Macromol Biosci 10(3) 265-270 Vanderhooft JL et al (2009) Rheological properties of cross-linked hyaluronan-gelatin hydrogels for tissue engineering. Macromol Biosci 9( l) 20—28... 

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