Graft Copolymerization of Methyl Methacrylate onto Natural Rubber by Microwave Irradiation

2010 ◽  
Vol 93-94 ◽  
pp. 39-42
Author(s):  
Sirichai Piyaauksornsak ◽  
Boonchoat Paosawatyanyong ◽  
Napida Hinchiranan
Keyword(s):  
Energy Consumption ◽  
Reaction Time ◽  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Chemical Modification ◽  
Natural Rubber ◽  
Methyl Methacrylate ◽  
1H Nmr Spectroscopy ◽  
Graft Copolymerization ◽  
Initiation System

The graft copolymerization is one chemical modification methods to improve natural rubber (NR)’s properties via both solution and latex phases. To enhance the polarity of NR, methyl methacrylate (MMA) was applied for graft copolymerization of NR in the presence of thermal or redox initiators. However, the conventional graft copolymerization generally spends long reaction time (ca. 6-8 h). Due to less energy consumption with faster heating rate, the microwave irradiation was used to induce graft copolmerization of MMA onto NR latex using redox initiation system. By comparing with the conventional grafting method at the same grafting properties, the graft copolymerization of MMA onto NR induced by microwave at 100 W spent the shorter reaction time ca. 15 min; whilst, the conventional method required the longer reaction time as 7 h. The influence of microwave power on the grafting properties was investigated. The structure of graft product was also analyzed by using FTIR and 1H NMR spectroscopy.

scholarly journals Graft Copolymerization of Methyl Methacrylate and Vinyltriethoxysilane onto Natural Rubber

2021 ◽  
Vol 31 (4) ◽  
pp. 55-60
Keyword(s):  
Nmr Spectroscopy ◽  
Natural Rubber ◽  
Methyl Methacrylate ◽  
Tensile Property ◽  
Graft Copolymer ◽  
Graft Copolymerization ◽  
Silica Particles ◽  
Grafting Efficiency

Preparation and characterization of natural rubber grafted with methyl methacrylate (MMA) and vinytriethoxysilane (VTES) were performed in the present work. Graft copolymerization of methyl methacryate was carried out in latex stage, and VTES was added during the graft copolymerization of MMA. FTIR and NMR spectroscopy were used to investigate the structure of graft copolymer and determination of conversion and grafting efficiency of MMA. It confirmed that the poly(methyl methacrylate) (PMMA) and silica particles (PVTES) were successfully formed in NR-graft-PMMA-PVTES graft copolymer. Conversions of MMA were about 90-100%; however, MMA grafting efficiency decreased as the MMA concentrations increased. Tensile property of NR-graft-PMMA-PVTES was found to improve compared with that of pure NR.

Graft copolymerization of methyl methacrylate and vinyltriethoxysilane binary monomers onto natural rubber

2021 ◽  
Vol 28 (7) ◽  
Author(s):  
Thuong Nghiem Thi ◽  
Ha Cao Hong ◽  
Yusof Nurul Hayati ◽  
Seiichi Kawahara
Keyword(s):  
Natural Rubber ◽  
Methyl Methacrylate ◽  
Graft Copolymerization

scholarly journals RADICAL INITIATED COPOLYMERIZATION OF METHYL METHACRYLATE AND ACRYLONITRILE IN PRESENCE OF IRON COMPLEXES

2021 ◽  
Vol 64 (4) ◽  
pp. 34-41
Author(s):  
Ruslan R. Galimullin ◽  
Natalya N. Sigaeva ◽  
Sergey V. Kolesov
Keyword(s):  
Free Radicals ◽  
Nmr Spectroscopy ◽  
Methyl Methacrylate ◽  
Metal Complexes ◽  
1H Nmr Spectroscopy ◽  
Initial Rate ◽  
Iron Complexes ◽  
Active Centers ◽  
Iron Metal ◽  
Effective Constants

This article represents data on the effect of organometallic iron complexes: ferrocene, dicarbonyl dimer of cyclopentadienyl iron and tricarbonyl cyclooctatetraene iron on the copolymerization of methyl methacrylate (MMA) and acrylonitrile (AN) initiated by benzoyl peroxide. It is shown that the introduction of metal complexes and their structure affect the initial rate of copolymerization, the form of the diagrams of the composition of the obtained copolymers, and the values of the effective constants of the relative activities of the comonomers in the copolymerization of methyl methacrylate and acrylonitrile (system metallocomplex of iron – peroxide benzoyl: ferrocene – peroxide benzoyl: rММА = 1.58; rАН= 0.08 in 60 °С; rММА = 1.30; rАН = 0.05 in 50 °С; dicarbonyl dimer cyclopentadienyl iron–peroxide benzoyl: rММА = 1.36; rАН = 0.06 in 60 °С; rММА = 1.09; rАН = 0.14 in 50 °С; tricarbonyl cyclooctatetraene iron -peroxide benzoyl: rММА = 1.08; rАН = 0.15 in 60 °С; rММА = 1.14; rАН = 0.05 in 50 °С; peroxide benzoyl: rММА = 1.11; rАН = 0.07 in 60 °С; rММА = 1.11; rАН = 0.07 in 50 °С). The proportions of triadic sequences of units in copolymers, experimentally determined from 1H NMR spectroscopy, are given, as well as the calculated proportions of dyads. The presence of iron metal complexes affects the distribution of the proportions of the triad and dyad sequences of units, as well as their microstructure in copolymers. These changes are explained by the formation of macromolecules, both with the participation of free radicals and the stereospecific coordination active centers of polymerization that are formed in the presence of iron complexes.

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