Synthesis of Ethylene Glycol Dimethacrylate-Methyl Methacrylate Copolymers, Determination of their Reactivity Ratios, and a Study of Dopant and Temperature Effects on their Conductivities

Abstract

Ultraviolet radiation was used as a photochemical initiator to synthesize ethylene glycol dimethacrylate-methyl methacrylate copolymers. Infrared spectroscopy was used to calculate reactivity ratios and to identify the type of copolymerization. The reactivity ratios of EGDMA and MMA were calculated as 0.6993 and 1.8635, respectively. The effect of lithium perchlorate as a dopant on copolymer conductivity and conversion was studied. The addition of dopant increased the conductivity of copolymers. For copolymers containing 5% MMA in the feed, dopant increased conductivity about 775 times; when the MMA percentage was 20% in the feed, dopant increased conductivity about 100 times. As MMA percentage increases in the copolymer, the conductivity values decrease from the mS to the µS region. This is consistent with the fact that PMMA has a lower conductivity than PEGDMA. The conductivity change of homopolymers and copolymers at various temperatures were studied. Both MMA and EGDMA polymers and their copolymers show a minimum in their conductivity vs. temperature graphs, indicating that they first act as a conductor and after a minimum temperature, become semiconductors and can be used to control current in electrical devices by temperature change. The measurement of conductivity change with time provided a new way to follow the kinetics of polymer/dopant reactions. The activation energy of interaction with dopant was calculated as 31.52 kJ/mol for MMA/EGDMA copolymers; for PEGDMA alone it was 54.7 kJ/mol. OPEN ACCESSPolymers 2010, 2 266

Viscosity and refractive index adjustment of poly(methyl methacrylate‐co‐ethyleneglycol dimethacrylate) for application in microoptics

“…EGDMA is an established crosslinker in methyl methacylate based copolymers, e.g. for the realization of polymer microspheres . Pure polyEGDMA possesses a glass transition temperature Tg around 74°C, if still unsaturated double bonds can be measured via FTIR, and 93°C if all reactive centers are polymerized …”

Membrane Emulsification Process as a Method for Obtaining Molecularly Imprinted Polymers

“…The adsorption band at 1455 cm −1 can be attributed to the bending vibration of the C–H bonds of the –CH 3 group [ 61 ]. The two bands at 1387 cm −1 and 752 cm −1 can be attributed to vibrations of the α-methyl group [ 61 , 62 ]. The two bands at 2990 cm −1 and 2952 cm −1 can be assigned to the C–H bond stretching vibrations of the –CH 3 and –CH 2 - groups, respectively [ 61 , 63 ].…”

A highly selective fluorescent chemosensor for Hg2+ based on a squaraine–bis(rhodamine-B) derivative: Part II

“…Effect of the PEGDMA polymer on SRB with Hg 2+ as a fluorescent-labeled additive Precipitation polymerization was used to prepare the PEGDMA-SRB polymer according to a previously reported procedure [96][97][98]. For the polymer particles to exhibit a chemosensing response, fluorescent-labeled additives are necessary.…”