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Magdy W Sabaa - One of the best experts on this subject based on the ideXlab platform.
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Vanillin–Schiff’s bases as organic thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride)
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
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vanillin schiff s bases as organic thermal Stabilizers and co Stabilizers for rigid poly vinyl chloride
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
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organic thermal Stabilizers for rigid poly vinyl chloride part xiii eugenol 4 allyl 2 methoxy phenol
Polymer Degradation and Stability, 2007Co-Authors: Magdy W Sabaa, Riham R MohamedAbstract:Abstract Eugenol (4-allyl-2-methoxy-phenol) has been examined as a thermal stabilizer and co-stabilizer for rigid PVC in air, at 180 °C. Its high stabilizing efficiency is detected by its high thermal stability value (Ts) when compared with some of the common reference Stabilizers used industrially such as dibasic lead carbonate, calcium–zinc soap and octyl tin mercaptide. Blending this organic stabilizer with some of the reference Stabilizers in different ratios had synergistic effect on both the induction period and the dehydrochlorination rate together with the longer extent of discolouration of PVC stabilized by eugenol as compared with the blank and the samples stabilized with reference commercial Stabilizers. A probable mechanism for the stabilizing action of eugenol has been proposed. The stabilizing efficiency is attributed partially to the stabilizer's ability to intervene in the radical chain degradation process of PVC and to the replacement of the labile chlorine atoms on PVC chains by a relatively more stable moiety of the organic stabilizer.
Riham R Mohamed - One of the best experts on this subject based on the ideXlab platform.
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Vanillin–Schiff’s bases as organic thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride)
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
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vanillin schiff s bases as organic thermal Stabilizers and co Stabilizers for rigid poly vinyl chloride
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
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organic thermal Stabilizers for rigid poly vinyl chloride part xiii eugenol 4 allyl 2 methoxy phenol
Polymer Degradation and Stability, 2007Co-Authors: Magdy W Sabaa, Riham R MohamedAbstract:Abstract Eugenol (4-allyl-2-methoxy-phenol) has been examined as a thermal stabilizer and co-stabilizer for rigid PVC in air, at 180 °C. Its high stabilizing efficiency is detected by its high thermal stability value (Ts) when compared with some of the common reference Stabilizers used industrially such as dibasic lead carbonate, calcium–zinc soap and octyl tin mercaptide. Blending this organic stabilizer with some of the reference Stabilizers in different ratios had synergistic effect on both the induction period and the dehydrochlorination rate together with the longer extent of discolouration of PVC stabilized by eugenol as compared with the blank and the samples stabilized with reference commercial Stabilizers. A probable mechanism for the stabilizing action of eugenol has been proposed. The stabilizing efficiency is attributed partially to the stabilizer's ability to intervene in the radical chain degradation process of PVC and to the replacement of the labile chlorine atoms on PVC chains by a relatively more stable moiety of the organic stabilizer.
Emad H Oraby - One of the best experts on this subject based on the ideXlab platform.
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vanillin schiff s bases as organic thermal Stabilizers and co Stabilizers for rigid poly vinyl chloride
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
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Vanillin–Schiff’s bases as organic thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride)
European Polymer Journal, 2009Co-Authors: Magdy W Sabaa, Riham R Mohamed, Emad H OrabyAbstract:Abstract Vanillin–Schiff’s bases (VSB) were examined as thermal Stabilizers and co-Stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180 °C. Their high stabilizing efficiency were shown by their high thermal stability value (Ts), which is the time elapsed for the detection of HCl gas, if compared with dibasic lead carbonate and cadmium–zinc soap reference Stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference Stabilizers in different ratios greatly lengthens the thermal stability and the extent of discoloration of the PVC. Condensation products of Vanillin with amines are very active biologically, besides having good complexation ability with metal ions. The Ni2+ and Co2+ complexes of VSB derivatives gave better thermal stability and less discoloration than the parent organic stabilizer. Also, blending these complexes with either of the used reference Stabilizers in different ratios gave better thermal stability and lower extent of discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the VSB derivatives, compared to blank PVC, PVC stabilized with reference Stabilizers and PVC stabilized with binary mixture of VSB derivatives with reference stabilizer. The stabilizing efficiency of Vanillin–Schiff’s base (VSB) derivatives is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer.
Qiang Zheng - One of the best experts on this subject based on the ideXlab platform.
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Influence of lanthanum stearate as a co-stabilizer on stabilization efficiency of calcium/zinc Stabilizers to polyvinyl chloride
Polymer Degradation and Stability, 2009Co-Authors: Long Fang, Yihu Song, Qiang ZhengAbstract:Abstract Influence of lanthanum stearate (LaSt3) as a co-stabilizer on stabilization efficiency of calcium stearate (Ca)/zinc glutarate (Zn) Stabilizers to polyvinyl chloride (PVC) at 180 °C in air was investigated. The results showed that combination of LaSt3 with Ca/Zn Stabilizers presented an obvious improvement of stabilization efficiency to PVC compared with the Ca/Zn Stabilizers. Moreover, addition of LaSt3 to the Ca/Zn Stabilizers could significantly enhance static stability time of PVC. Incorporation of 2 phr LaSt3 co-stabilizer to PVC containing 3 phr Ca/Zn Stabilizers resulted in marked increase of onset degradation temperature and reductions in average degradation rate as well as the dynamic storage modulus (G′) and loss modulus (G″) at 180 °C. Influence of Ca/Zn ratio on tensile strength of PVC in the absence or in the presence of LaSt3 was discussed in detail. At low Ca/Zn ratios LaSt3 had an obvious improvement in the tensile strength, while at high Ca/Zn ratios this effect became inconspicuous.
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influence of lanthanum stearate as a co stabilizer on stabilization efficiency of calcium zinc Stabilizers to polyvinyl chloride
Polymer Degradation and Stability, 2009Co-Authors: Long Fang, Yihu Song, Xiaonan Zhu, Qiang ZhengAbstract:Abstract Influence of lanthanum stearate (LaSt3) as a co-stabilizer on stabilization efficiency of calcium stearate (Ca)/zinc glutarate (Zn) Stabilizers to polyvinyl chloride (PVC) at 180 °C in air was investigated. The results showed that combination of LaSt3 with Ca/Zn Stabilizers presented an obvious improvement of stabilization efficiency to PVC compared with the Ca/Zn Stabilizers. Moreover, addition of LaSt3 to the Ca/Zn Stabilizers could significantly enhance static stability time of PVC. Incorporation of 2 phr LaSt3 co-stabilizer to PVC containing 3 phr Ca/Zn Stabilizers resulted in marked increase of onset degradation temperature and reductions in average degradation rate as well as the dynamic storage modulus (G′) and loss modulus (G″) at 180 °C. Influence of Ca/Zn ratio on tensile strength of PVC in the absence or in the presence of LaSt3 was discussed in detail. At low Ca/Zn ratios LaSt3 had an obvious improvement in the tensile strength, while at high Ca/Zn ratios this effect became inconspicuous.
Youwei Yao - One of the best experts on this subject based on the ideXlab platform.
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effect of thermal Stabilizers composed of zinc barbiturate and calcium stearate for rigid poly vinyl chloride
Polymer Degradation and Stability, 2011Co-Authors: Youwei YaoAbstract:Abstract Zinc barbiturate [Zn(H 2 L) 2 ·2H 2 O, abbreviated as ZnL 2 ] was synthesized by a precipitation method in aqueous solution, and investigated as a co-stabilizer with calcium stearate (CaSt 2 ) for rigid poly(vinyl chloride) (PVC) by the discoloration test and the dehydrochlorination test at 180 °C. ZnL 2 exhibits high stabilizing effect with excellent initial colour of PVC films. In comparison with the synergistic effect of CaSt 2 /ZnSt 2 Stabilizers, the CaSt 2 /ZnL 2 Stabilizers in mass ratios ranging from 0.3/1.2 to 0.6/0.9 exhibit better synergistic effect. Moreover, PVC films stabilized by CaSt 2 /ZnL 2 show better initial colour with the addition of dibenzoyl methane as an auxiliary stabilizer. The mechanism of stabilizing action of ZnL 2 is also proposed. ZnL 2 may replace the labile chlorine atoms to interrupt the formation of conjugated double bonds in PVC chains, and act as the absorber of hydrogen chloride to restrain the self-catalytic dehydrochlorination.
