Cenospheres are produced in very large amount in thermal power plants. They are always looked upon as fillers used to reduce the density and cost of the polymer. If cenosphere particles are allowed to remain properly ...Cenospheres are produced in very large amount in thermal power plants. They are always looked upon as fillers used to reduce the density and cost of the polymer. If cenosphere particles are allowed to remain properly dispersed by taking it in lower concentration, significant improvement in its mechanical, thermal, electrical, crystallinity, colorimetric and morphological properties are expected. To make it happen, epoxy/cenosphere composites were prepared, having lower concentration of cenosphere. Concentration of cenosphere in epoxy, cured with triethylenetetramine, was changed as 0, 3, 5, 7 and 10. Tensile Strength, Tensile Modulus, Percentage Elongation at Break and Crystallinity decreased, whereas, Flexural Strength and Flexural Modulus were found to have increased by 50% and above 100% respectively at 7 phr loading of cenosphere in epoxy. Thermal and electrical stability also increased with increase in concentration of cenosphere in the epoxy, however, the samples became blackish with increased addition of cenosphere. Using SEM analysis it was found that, cenospheres were properly and uniformly dispersed at 7 phr concentration and formed aggregates at 10 phr concentration.展开更多
A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylen...A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylene glycol methyl ether(PM)solution for chain extension reaction.A hydrophilic andflexible polyether seg-ment was introduced into the hardener molecule.The effects of TETA/DGEPG,reaction temperature and reaction time on the epoxy conversion of polyethylene glycol diglycidyl ether(DGEPG)were studied.In addition,several alternate strategies to add epoxy resin to the high-speed dispersion machine and synthesize MEA DGEBA adduct(without catalyst and with bisphenol A diglycidyl ether epoxy resin)were compared.It was found that the higher the molecular weight of triethylenetetramine,the longer the chain segment of the surface active molecule.When the equivalence ratio of amine hydrogen and epoxy group is low,the stability of lotion is good.When the ratio of amine hydrogen to epoxy group is large,the content of triethylenetetramine is small.The main objective of this study is the provision of new data and knowledge for the development of new materials in the coating and electronic industry.展开更多
Polyamine-based scavenger resins containing 2, 3 and 4 nitrogen atoms have been prepared and their comparative efficacy to scavenge appropriate electrophilic chemicals (acids, acid chlorides, isocyanates and aldehydes...Polyamine-based scavenger resins containing 2, 3 and 4 nitrogen atoms have been prepared and their comparative efficacy to scavenge appropriate electrophilic chemicals (acids, acid chlorides, isocyanates and aldehydes) from solutions has been studied. As expected, the scavenging efficiency is directly proportional to the number of nucleophic nitrogens present on the resin. The results have been compared with the performance of the popular scavenger resin, namely, tris(2-aminoethyl)amine resin, to conclude that the low-cost polyamine resins now prepared can be conveniently used as effectively as the expensive commercial product.展开更多
文摘Cenospheres are produced in very large amount in thermal power plants. They are always looked upon as fillers used to reduce the density and cost of the polymer. If cenosphere particles are allowed to remain properly dispersed by taking it in lower concentration, significant improvement in its mechanical, thermal, electrical, crystallinity, colorimetric and morphological properties are expected. To make it happen, epoxy/cenosphere composites were prepared, having lower concentration of cenosphere. Concentration of cenosphere in epoxy, cured with triethylenetetramine, was changed as 0, 3, 5, 7 and 10. Tensile Strength, Tensile Modulus, Percentage Elongation at Break and Crystallinity decreased, whereas, Flexural Strength and Flexural Modulus were found to have increased by 50% and above 100% respectively at 7 phr loading of cenosphere in epoxy. Thermal and electrical stability also increased with increase in concentration of cenosphere in the epoxy, however, the samples became blackish with increased addition of cenosphere. Using SEM analysis it was found that, cenospheres were properly and uniformly dispersed at 7 phr concentration and formed aggregates at 10 phr concentration.
基金This work is financially supported by a University-Level Doctoral Research Start-Up Fund in 2019.
文摘A triethylenetetramine epoxy mixture was synthesized through the reaction of a low-molecular-weight liquid epoxy resin with triethylenetetramine(TETA).Then triethyltetramine(TETA)was injected dropwise into a pro-pylene glycol methyl ether(PM)solution for chain extension reaction.A hydrophilic andflexible polyether seg-ment was introduced into the hardener molecule.The effects of TETA/DGEPG,reaction temperature and reaction time on the epoxy conversion of polyethylene glycol diglycidyl ether(DGEPG)were studied.In addition,several alternate strategies to add epoxy resin to the high-speed dispersion machine and synthesize MEA DGEBA adduct(without catalyst and with bisphenol A diglycidyl ether epoxy resin)were compared.It was found that the higher the molecular weight of triethylenetetramine,the longer the chain segment of the surface active molecule.When the equivalence ratio of amine hydrogen and epoxy group is low,the stability of lotion is good.When the ratio of amine hydrogen to epoxy group is large,the content of triethylenetetramine is small.The main objective of this study is the provision of new data and knowledge for the development of new materials in the coating and electronic industry.
文摘Polyamine-based scavenger resins containing 2, 3 and 4 nitrogen atoms have been prepared and their comparative efficacy to scavenge appropriate electrophilic chemicals (acids, acid chlorides, isocyanates and aldehydes) from solutions has been studied. As expected, the scavenging efficiency is directly proportional to the number of nucleophic nitrogens present on the resin. The results have been compared with the performance of the popular scavenger resin, namely, tris(2-aminoethyl)amine resin, to conclude that the low-cost polyamine resins now prepared can be conveniently used as effectively as the expensive commercial product.
