Hydrophobicity Modification of Water-soluble Polymers

Polymer modification technique is a valuable synthetic approach which leads to modified polymers with unique composition، structure، and properties that cannot be readily achieved by direct polymerization of monomers. Since 1990، polymer modification technique has become a most important method for improving the properties of polymers and extending the range of their application. Nowadays، the modified polymers such as cellulose and poly acrylic acid are available on a commercial scale in the world. Hydrophobically modified polymers (HMPs) have attracted a great deal of interest because of their unusual rheological properties. These polymers consist of watersoluble hydrophilic backbones and a small amount (typically < 2-5 mol%) of covalently bonded hydrophobic moieties called «stickers». The molecular architecture as well as the characteristics of the hydrophilic chain and stickers can vary widely. Therefore، the diverse structural architectures of these modified polymers (random، block or hydrophobically endcapped) produce diverse physicochemical properties، which lead to useful applications in pharmaceutics، dispersants، thickening agents، cosmetics and oil recovery.