Samir Biswas

Photopolymerization of methyl methacrylate using tetrahydrofuran sulphur dioxide complex as photoinitiator

Abstract Photopolymerization of MMA in visible light was studied at 40 using THF-SO2 complex as the photoinitiator. Initiator exponent was 0.19 and monomer exponent lay between 1.0 and 1.5, depending on thenature of solvent. Analysis of kinetic and other data indicate that the polymerization proceeds by a radical mechanism and termination is initiator dependent. Chain termination via degradative chain (initiator) transfer appears to be significant feature.

Aqueous Polymerization of Methyl Methacrylate Initiated by Pyridine-Sulfur Dioxide Complex

Abstract The aqueous polymerization of MMA was studied kinetically at 40° C using low concentrations of Py-SO2 complex as initiator. For [Py-SO2] 2 × 10−2 mol/L, Rp ∞ [Py-SO2]0,0[M]1.08. Polymerization is considered to proceed by a radical mechanism. The radical generation or the initiation step is believed to proceed through equilibrium complexation between the Py-SO2 complex and monomer molecules. For [Py-SO2] < 2 × 10−2 mol/L, the polymerization is characterized by bimolecular termination. Above this [Py-SO2], chain termination by a degradative initiator transfer process assumes prominence.

Photopolymerization of methyl methacrylate using a combination of michler's ketone and benzoyl peroxide as photoinitiator

Abstract A combination of Michlers ketone and benzoyl peroxide was used as photoinitiator for photopolymerization of methyl methacrylate at 40°. Spectrophotometric analysis indicated equilibrium complexation between the initiator components; the complex is considered to be the actual initiating species, giving free radicals by photo-decomposition. The observed initiator exponent of 0.21 and monomer exponent of > I in various solvents reveal non-ideality in the photopolymerization kinetics. The non-idealities are interpreted in terms of initiator dependent chain termination mainly by primary radicals, in addition to the usual bimolecular termination.

Kinetic Investigation on the Photopolymerization of Methyl Methacrylate Using Iodine Trichloride as Initiator

Abstract The photopolymerization of MMA in visible light was studied at 45°C using IC13 as the photoinitiator. The initiator exponent was found to be 0.16 and the monomer exponent varied between 1.0 to 1.50, depending on the nature of the solvent. Analysis of the data revealed that the polymerization was induced by a free radical mechanism. Nonideality of the kinetics was explained on the basis of 1) Monomer-dependent chain initiation and 2) Initiator-dependent chain termination via degradative initiator transfer.

Use of an Internal Keto-Imino Compound as the Photoinitiator in the Polymerization of Methyl Methacrylate

Abstract Photopolymerization of MMA in visible light was studied at 40°C using acridone as the photoinitiator. The polymerization was found to proceed via a free radical mechanism and the radical generation process was considered to follow an initial complexation reaction between monomer and acridone. Kinetic data indicated a lower order dependence of Rp on the initiator concentration (initiator exponent < 0.5). Initiator-dependent chain termination was significant along with the usual bimolecular mode of chain termination. The monomer exponent varied from about 1.0 to 1.5, depending on the nature of the solvent used. The nonidealities in this case were also analyzed.

Photopolymerization of Methyl Methacrylate Initiated by Pyridine-Sulfur Dioxide Charge Transfer Complex in the Presence of Carbon Tetrachloride

Photopolymerization of methyl methacrylate in visible light was studied at 40°C using a pyridine-sulfur dioxide charge transfer complex as the initiator in the presence of carbon tetrachloride. In ...