Polymers structure-activity relationships

An area of great interest in the polymer chemistry field is structure-activity relationships. In the simplest form, these can be qualitative descriptions, such as the observation that branched polymers are more biodegradable than straight-chain polymers. Computational simulations are more often directed toward the quantitative prediction of properties, such as the tensile strength of the bulk material. 

Van de Wetering, P., Moret, E.E., Schuurmans-Nieuwenbroek, N.M.E., Van Steenbergen, M.J. and Hennink, W.E. (1999a) Structure-activity relationships of water-soluble cationic methacrylate/methacrylamide polymers for nonviral gene delivery. Bioconjug. Chem., 10, 589-597. 

Chemical programming of polymers has proven to be a crucial tool in mimicking virus-like features. Thus, alterations in polymer structure and conformation can be correlated to transfection efficiency and cytotoxicity. It has to be considered that the better polymer structure is defined, the more detailed study of structure-activity relationships is possible. First approaches towards better defined polymer structure with narrow molecular weight distribution have been made by PAE and pseudo-dendrimer synthesis already discussed in Sect. 4.1. 

An advantage of defining the problem in this manner is that the partition coefficient has become a central property in quantitative structure-activity relationships (QSAR) and a large data base of P values is available in the medicinal chemistry literature (22-24). In particular, if a correlation (Equation 15) between the polymer-water and octanol-water partition coefficients can be established for a series of solutes, it becomes possible to utilize log P (oc-tanol/water) value as a reference point from which to calculate the polymer-water value. 

The development of polythiophenes since the early 1980s has been extensive. Processible conducting polymers are available and monomer derivatization has extended the range of electronic and electrochemical properties associated with such materials. Problem areas include the need for improved conductivity by monomer manipulation, involving more extensive research using structure—activity relationships, and improved synthetic methods for monomers and polymers alike, which are needed to bring the attractive properties of polythiophenes to fruition on the commercial scale. 

In the field of isospecific propylene polymerization, systematic structure-activity relationship studies of metalloeenes have shown that the combination of 2-alkyl and 4-aryl substitution is cmcial for a technically suitable catalyst performance (high catalytic activity, excellent stereoselectivity, high melting point of the polymer, certain copolymer properties, etc.) [7, 8]. Consequently, there is a consider-... 

Materials Studio A software for modeling and simulation of crystal structure, polymer properties, and structure-activity relationships (http //www.accelrys.com/products/mstudio)... 

C. M., Simpson, M., Ansari, A. M., Harris, T. M., and Ekwuribe, N. Structure-activity relationship of insulin modified with amphiphilic polymers. AAPS PharmSci 1(1 Suppl.), 1998. 

QSAR Quantitative structure-activity relationships (term used for ordinary molecules). QSPR Quantitative structure-property relationships (term used for polymers). 

Additive (group contribution) methods have a long tradition of successful use in predicting the properties of both ordinary molecules and macromolecules (polymers). They have formed the backbone of the quantitative structure-activity relationships (QSAR) [1,2] used to predict the chemical reactivity and the biological activity of molecules in medicinal and agricultural chemistry. They have also been used extensively in many quantitative structure-property relationships (QSPR) developed for the physical and chemical properties of polymers. 

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