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Ganeschandra Pal

Bio: Ganeschandra Pal is an academic researcher from University of Calcutta. The author has contributed to research in topics: Photopolymer & Monomer. The author has an hindex of 3, co-authored 4 publications receiving 27 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the authors studied the photopolymerization of methyl methacrylate (MMA) using near UV/visible light at 40°C and employing the morpholine (MOR) −bromine (Br 2 ) charge transfer (CT) complex as the photoinitiator.

12 citations

Journal ArticleDOI
TL;DR: In this paper, the authors studied the polymerization of the vinyl monomer (M) of methyl methacrylate (MMA) by using near-UV/visible light at 40°C and employing a morpholine (MOR)-sulfur dioxide (SO 2 ) charge transfer (C-T complex) as the photoinitiator.
Abstract: Photopolymerization of the vinyl monomer (M) of methyl methacrylate (MMA) was kinetically studied by using near-UV/visible light at 40°C and employing a morpholine (MOR)-sulfur dioxide (SO 2 ) charge-transfer(C-T complex as the photoinitiator. The rate of polymerization (R P ) was found to be dependent on the morpholine: sulfur dioxide mole ratio; the 1: 2 (MOR-SO 2 ) complex acted as the latent initiator complex C which underwent further complexation with the monomer molecules to give the actual initiating complex I. Using the 1: 2 (MOR-SO 2 ) C-T complex as the latent initiator, the observed kinetics may be expressed as R P [MOR-SO 2 ] 0.27 [M] 1.10 . Benzoquinone behaved as a strong inhibitor. Polymers obtained tested positive for the incorporation of a sulphonate-type end group. Polymerization followed a radical mechanism. Kinetic nonideality as revealed by a low initiator exponent and monomer exponent of greater than unity was explained on the basis of a prominent primary radical termination effect.

11 citations

Journal ArticleDOI
TL;DR: In this paper, PCC-induced photopolymerisation of the vinyl monomer (M) methyl methacrylate (MMA) was studied at 40 °C using pyridinium chlorochromate (PCC) as the photoinitiator.

4 citations

Journal ArticleDOI
TL;DR: In this article, the rate of polymerization was dependent on morpholine/chlorine mole ratio, and the 1 : 2 (MOR-Cl2) C-T complex acted as the latent initiator complex, C, which underwent further complexation with the monomer molecules to give the actual initiators complex, I.
Abstract: Polymerization of methyl methacrylate (MMA) was kinetically studied under photo condition using near UV visible light at 40°C and employing morpholine (MOR)–chlorine (Cl2) charge transfer (C-T) complex as the photoinitiator. The rate of polymerization (Rp) was dependent on morpholine/chlorine mole ratio; the 1 : 2 (MOR–Cl2) C-T complex acted as the latent initiator complex, C, which underwent further complexation with the monomer molecules to give the actual initiator complex, I. Using 1 : 2 (MOR-Cl2) C-T complex as the latent initiator, the initiator exponent evaluated for bulk photopolymerization of MMA was 0.071 and monomer exponent determined from studies of photopolymerization in benzene diluted system was 1.10. Benzoquinone behaved as a strong inhibitor and the polymers tested positive for the incorporation of chlorine atom end groups. Polymerization followed a radical mechanism. Kinetic nonideality as revealed by low (≪0.5) initiator exponent and a monomer exponent of greater than unity were explained in terms of primary radical termination effect. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1681–1687, 1997

1 citations


Cited by
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Journal ArticleDOI
12 Jan 2002
TL;DR: In this article, the authors define photopolymerization as the initiation by light of a chain polymerization process, i.e., the increase of molecular weight caused by the light of polymerization.
Abstract: By the term photopolymerization we mean the initiation by light of a chain polymerization process. In the more general sense, photopolymerization implies the increase of molecular weight caused by ...

94 citations

Journal ArticleDOI
TL;DR: In this article, charge transfer complexes (CTC) between N-aromatic amines (donors) and iodonium salts (acceptors) are used as photoinitiating systems (PIS) for the polymerization of clear methacrylate formulations under a 405 nm LED irradiation.
Abstract: Charge transfer complexes (CTC) between N-aromatic amines (donors) and iodonium salts (acceptors) are used here as photoinitiating systems (PIS) for the polymerization of clear methacrylate formulations under a 405 nm LED irradiation. Outstandingly, a complete spatial and temporal resolution is kept for 50 μm resolved 3D printed photopolymers at 405 nm (50 μm being the size of the printing laser used here). Photocuring of a high thickness (31 cm) is also possible. The photopolymerization propagation is rationalized and interpreted from both experimental (using thermal imaging experiments) and predicted data. An experimental/molecular modeling study also attempts to rationalize the CTC structure/reactivity/efficiency relationships. These systems are commercially available, stable, and metal-free and have a low toxicity.

81 citations

Journal ArticleDOI
TL;DR: In this paper, an update on charge transfer complexes (CTCs) as photoinitiating systems for photopolymerization applications is provided with examples of CTC-specific structure/reactivity/efficiency relationships.

61 citations

Journal ArticleDOI
TL;DR: In this article, a novel strategy for the preparation of extremely thick composites by photochemical and/or thermal free radical polymerization (FRP) under low-energy consumption visible light emitted diodes (LEDs) is described.
Abstract: A novel strategy for the preparation of extremely thick composites by photochemical and/or thermal free radical polymerization (FRP) and/or cationic polymerization (CP) under low-energy consumption visible light emitted diodes (LEDs) is described. The approach is based on the use of charge transfer complexes (CTCs) formed between N-aromatic amines (donors) and iodonium salts (Iod, acceptors). Remarkably, it is demonstrated for the first time that these CTCs can be used as thermal initiators for free radical polymerization (FRP) initiation with performances comparable to dibenzoyl peroxide-based systems. The decomposition temperature of these CTC thermal initiators can be modulated through the selection of the amine, providing much safer conditions for synthesis, storage, and handling than that of the classical thermal initiators. A good stability in resin is also noted.

41 citations