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Abstract In the present work, di-(tri-n-butyltin) itaconate (TBTI) was prepared to .study its copolymerization and terpolymerization reactions with alkyl acrylates and methacrylates, styrene, acrylonitrile and N-vinyl-2-pyrrolidinone. Copolymerization reactions of TBTI with methyl acrylate (MA), ethyl acrylate (EA) , n-butyl acrylate (BA), 2-chloroethyl acrylate (CLEA), methyl methacrylate (MMA), allyl methacrylate (AHA), acrylonitrile (AN), styrene (ST) and N-vinyl-2-pyrrolidinone (NVP) were studied and the copolymer composition of each sample was calculated from tin analysis. The monomer reactivity ratios for the systems studied were determined according to the Fineman-Ross and Kelen-Tudos methods, as illustrated in the following Table: System Fineman-Ross method ICe1en- Tudas method TBTI-MA ~- 0.419+0.052 0.592+0.027 0.387+0.019 0.671+0.022 TBTI-EA 0.422+0.053 0.901+0.034 0.555+0.018 0.958+0.021 \- TBTI-BA 0.422+0.065 0.910+0.047 0.521+0.022 0.957+0.027 TBTI-CLEA 0.391+0.021 0.683+0.012 0.391+0.011 0.684+0.013 TBTI-tI4A 0.230+0.098 1.578+0.100 0.182+0.083 1.553+0.054 TBTI-AMA 0.038+0.087 1.075+0.092 0.068+0.006 1’.052+0.049 TBTI-AN 0.558+0.089 0.471+0.048 0.441+0.054 0.425+0.039 TBTI-ST 0.115+0.042 0.652+0.029 0.156+0.035 0.645+0.022 TBTI-NVP 0.050+0.017 0.197+0.020 0.033+0.013 0.185+0.043 Copolymerization reactions of TBTI with methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-chloroethyl acrylate, acrylonitrile, styrene and N-vinyl-2- pyrrolidinone was found to give azeotropic copolymers at 0! 35, 0•09, 0.08, 0~34, 0•51, 0.30 and 0.46 mo 1e fract~on, respectively, while the studied copolymerization reactions of TBTI with methyl methacrylate and allyl methacrylate gave no azeotropi,c copolymers. Also, the copolymerization parameters for TBTI-ST and TBTI-MMA systems were determined from lH-NMR spectroscopy. The monomer reac~ivity ratio values obtained in each case were formed to be rl = 0.228, r2 = 0.677 and rl = 0.~20, r2 = 1.635 Which are in agreement with those obtained from tin analysis. The sequence distribution of the triad fractions of each system were calculated from reactivity ratios and compared with those obtained from IH-NMR data. Azeotropy in binary and ternary copolymerization reactions of di-(tri-n-butyltin) itaconate with acrylic acid esters, t styrene and acrylonitrile was investigated. Thus, the azeotropic composition of the binary systems TBTI-MA, TBTI-EA, TBTI-BA, TBTI-ST and TBTI-AN Fl = 35, 9, 8, 30 and 51 Mol’, respectively) were polymerized to several degrees coverLnq a wide range of conversions and it indicates that for each system the copolymer composition remains constant up to high conversions. Four terpolymer systems were prepared by reaction of TBTI with AN and each of MA, EA, BA or ST. A computer program based on the terpolymer-composition equation was used to facilitate the calculations of the ternary monomer-polymer composition relationship and to stu~y the unitary, binary and ternary azeotropies of the various systems. Also, I.pseudo-azeotropic” regions were identified where the deviation between monomer and polymer compositions is very small. Ternary azeotropic compositions for TBTI-MA-AN and TBTI-EA-AN systems were found to be 37: 48: 15 and 9: 80: 11 molt, respectively. The azeotropic terpolymer compositions were polymerized to several conversions covering a wide range. The experimental results for the azeotropic terpolymer compositions were in good agreement with the theoretical values. Also, selective feed compositions correspopding to unitary and binary azeotropy for each terpolymer system were polymerized to low conversions. The experimental t.er poLyme.r compositions agreed well with the predicted values which indicate the correctness of the determined monomer reactivity ratio values. It was concluded that the free redical terpolymerization reactions of the systems studied followed the classical copolymerization theory. The structure of the prepared co- and terpolymers was investigated by l.R. spectroscopy. |