determination of intrinsic viscosity of polymers

#Determination of intrinsic viscosity of polymers series
#Determination of intrinsic viscosity of polymers free

Gee also measured the solubility parameter by determining the degree of swelling of cross-linked polymers in various solvents, but difficulties were presented because of the poor sensitivity of the measuring technique.

#Determination of intrinsic viscosity of polymers series

It is therefore essential in working with polymeric blends of PVAc that the solubility parameter be accurately and precisely known.īurrell developed a method of determining the solubility parameter of a polymer by measuring the solution properties in a series of solvents and then relating its solubility parameter to that of the solvent in which the polymer is soluble in all proportions. The solubility parameter (δ) is an unique physical property of any polymeric material and can be a useful guide to understanding the miscibility or compatibility of two polymeric substances. Understanding the physical and chemical properties of PVAc is essential in understanding its functional uses in bulk, solution or in a commercial product. PVAc is considered a thermoplastic, atatic, amorphous, non-toxic polymer whose bulk properties range from a gummy solid at low molecular weight to a brittle leathery material at high molecular weight. PVAc is also the precursor for making Polyvinyl Alcohol (PVOH), the single largest volume water-soluble polymer in the world. PVAc is an extremely important commercial polymer used as the major polymeric component in some water-based latex paints, wood adhesives, paper binders and as a food masticatory component in chewing and bubble gums.

#Determination of intrinsic viscosity of polymers free

It is usually produced by the free radical polymerization of vinyl acetate either in a non-aqueous solvent or as an emulsion. The most important polymer in this family is Polyvinyl Acetate (PVAc). Polyvinyl alkyl ester of carboxylic acids are a family of macromolecules in which the side chain esters (pendant groups) increase in molar mass and hydrophobicity and decrease in structural polarity as the number of carbons in the carboxylic acid increases. Our experimentally determined solubility parameter was 9.35 (cal/cm 3) 1/2 which compared well with the computational values obtained by Hoy (9.56), Small (9.45) and Van Krevelen (9.27). The Mark-Houwink constants for PVAC in the four solvents were also experimentally determined. We also estimated the solubility parameter using the principles of group additivity contribution due to the atoms, groups and bonds present in PVAc based on the theories of Small, Hoy, and Van Krevelen. We have experimentally determined the solubility parameter of food grade PVAc by measuring the intrinsic viscosity of several different molecular weight PVAc samples (ranging from 11K -75K Daltons) in four different solvents (acetone, methanol, tetrahydrofuran, toluene,) at 25☌ using glass capillary viscometry. It is therefore essential in working with polymeric blends of PVAc that the experimental solubility parameter be accurately and precisely known. The Solubility Parameter (δ) is a unique physical property of any polymeric material and can be a useful guide to understanding the miscibility or compatibility of two polymeric substances.