title: Stannic chloride-para toluene sulfonic acid as a novel catalyst-co-catalyst system for the designing of hydroxyl terminated polyepichlorohydrin polymer: Synthesis and characterization.
abstract: Hydroxy terminated polyepichlorohydrin (PECH) was synthesized in good yield (85-88%) with improved functionality (2.01-2.53) and desired number average molecular weight (∼3000), using a novel catalyst-co-catalyst combination. The effect of various molar ratios (4-12) of p-toluenesulphonic acid and SnCl4 on molecular weight of PECH was investigated. Different polymerization conditions like temperature, time and monomer addition rates were found to have pronounced effect on molecular weight, polydispersity and functionality of the products. The molecular weight distribution and polydispersity of the synthesized polymers were determined by Gel permeation chromatography (GPC). Absolute value of Number average molecular weight (Mn) was established with vapor pressure osmometry and structural elucidations were carried out by FT-IR and NMR spectroscopic techniques. Terminal Hydroxyl groups were quantified by acetylation method and functionality was derived from hydroxyl value and Mn.
authors.affiliation: Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Ahmad
authors.affiliation: Department of Chemistry, University of Science & Technology, Bannu, Pakistan; Department of Chemistry, COMSATS Institute of Information Technology, Abbottabad 22060, Pakistan. Electronic address: m.siraj09@yahoo.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Sirajuddin
authors.affiliation: Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan. Electronic address: zareen_a@qau.edu.pk.
authors.forename: Zareen
authors.initials: Z
authors.lastname: Akther
authors.affiliation: Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
authors.forename: Waqar
authors.initials: W
authors.lastname: Ahmad
keywords: Cationic ring opening polymerization; Epichlorohydrin polymerization; Polyepichlorohydrin; Polyether polyol