This study investigated the viscoelastic and rheometeric properties of PVC stabilized with tannin-Ca complex as totally bio-based thermal stabilizer. Dynamic mechanical thermal analysis (DMTA) used to characterize the...This study investigated the viscoelastic and rheometeric properties of PVC stabilized with tannin-Ca complex as totally bio-based thermal stabilizer. Dynamic mechanical thermal analysis (DMTA) used to characterize the viscoelastic properties of PVC samples obtained by thermal mixing of PVC with three composition percentages (1.0, 2.0, and 3.0) part per hundred ratios (phr) of tannin-Ca complex with this polymer. The torque rheometery test used to monitor the effect of tannins derivative on the thermal stability and mixing properties of PVC formulations during samples processing. For that purpose, PVC sample with 2 phr commercial thermal stabilizer (Reapak B-NT/ 7060) was used for comparison and considered as reference samples. Before the glass transition temperature of PVC at 30°C - 60°C, the DMTA curves show that the values of storage modulus and tan delta of PVC samples stabilized with tannin derivative were very similar with those of PVC sample stabilized with commercial thermal stabilizer. The glass transition temperature (Tg) of PVC stabilized with commercial thermal stabilizer and with tannin-Ca complex occurred at about 76°C. In a sequence, after the glass transition region of PVC samples, the DMTA scans confirmed that the PVC samples with 2 phr tannin-Ca complex have relatively longer flowing stage which occurs at lower temperatures by 18°C per that of PVC sample stabilized with commercial stabilizer. Global results of the torque rheometery which have suitable plateau stages and the DMTA show that the processing thermal stability and thermal flexibility of PVC are clearly increased with the incorporation of tannin-Ca complex. All the PVC formulations with tannins-Ca complex show excellent viscoelastic properties which were found to be slightly best or much closed to those obtained for PVC stabilized with commercial thermal stabilization.展开更多
The influences ofphosphite and epoxy soybean oil in combination with liquid calcium/zinc isocaprylates on the thermal stability of flexible poly （vinyl chloride） were studied. The stabilizing effect of poly （vinyl ...The influences ofphosphite and epoxy soybean oil in combination with liquid calcium/zinc isocaprylates on the thermal stability of flexible poly （vinyl chloride） were studied. The stabilizing effect of poly （vinyl chloride） was evaluated by Congo red method, thermoaging test and Thermogravimetric-differential Scanning Calorimetry （TG-DSC）. The results showed that the addition of the phosphite or epoxy soybean oil improved the thermal stability of PVC with the calcium/zinc isocaprylates stabilizing system, especially epoxidied soybean oil exhibited a remarkable effect, and the synergism on PVC thermal stability for 3：2 phenyl dioctyl phosphite to epoxidized soybean oil weight ratio was acquired. Accordingly, the rapid mass loss in TG curve occured between 258.9 ℃ and 334.4 ℃, which corresponded to the enthalpy of the pyrogenation of 609.2 J/g. It was also found that the stabilized PVC of the best ratio gave better mechanical and processing properties.展开更多
介绍了CZ-900A型Ca/Zn复合热稳定剂在PVC制品中的应用效果,报道了其热稳定性能、流变性能和环保性能,并与目前国内同类产品进行了比较。试验结果表明:CZ-900A型Ca/Zn复合热稳定剂可以抑制Z n C l2对PVC的催化降解和"锌烧",具...介绍了CZ-900A型Ca/Zn复合热稳定剂在PVC制品中的应用效果,报道了其热稳定性能、流变性能和环保性能,并与目前国内同类产品进行了比较。试验结果表明:CZ-900A型Ca/Zn复合热稳定剂可以抑制Z n C l2对PVC的催化降解和"锌烧",具有较优的静态热稳定性、动态热稳定性和流变性能,且产品不含铅、镉等重金属,是新一代绿色环保型热稳定剂。展开更多
： The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the therma...： The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the thermal decomposition process,Mg-Al-CO3 hydrotalcite exhibits two steps- desorption of interlayer water occurs at 200℃ ,followed by dehydroxylation of the brucite-like layers and loss of carbonate at 400℃ ,Zn-Al-CO3 hydrotalcite decomposes in one step-the desorption of interlayer water, structural water and carbon dioxide occurred at the same time at 200℃ . The results of a theoretical study indicate that the bond strengths of OH-CO3-OH and OH-H2O-CO3-OH in Mg-Al-CO3 hydrotalcite are stronger than those in Zn-Al-CO3 hydrotalcite.It has been shown that the thermal stability of Mg-Al-CO3 hydrotalcite is higher than that of Zn-Al-CO3 hydrotalcite.展开更多
文摘This study investigated the viscoelastic and rheometeric properties of PVC stabilized with tannin-Ca complex as totally bio-based thermal stabilizer. Dynamic mechanical thermal analysis (DMTA) used to characterize the viscoelastic properties of PVC samples obtained by thermal mixing of PVC with three composition percentages (1.0, 2.0, and 3.0) part per hundred ratios (phr) of tannin-Ca complex with this polymer. The torque rheometery test used to monitor the effect of tannins derivative on the thermal stability and mixing properties of PVC formulations during samples processing. For that purpose, PVC sample with 2 phr commercial thermal stabilizer (Reapak B-NT/ 7060) was used for comparison and considered as reference samples. Before the glass transition temperature of PVC at 30°C - 60°C, the DMTA curves show that the values of storage modulus and tan delta of PVC samples stabilized with tannin derivative were very similar with those of PVC sample stabilized with commercial thermal stabilizer. The glass transition temperature (Tg) of PVC stabilized with commercial thermal stabilizer and with tannin-Ca complex occurred at about 76°C. In a sequence, after the glass transition region of PVC samples, the DMTA scans confirmed that the PVC samples with 2 phr tannin-Ca complex have relatively longer flowing stage which occurs at lower temperatures by 18°C per that of PVC sample stabilized with commercial stabilizer. Global results of the torque rheometery which have suitable plateau stages and the DMTA show that the processing thermal stability and thermal flexibility of PVC are clearly increased with the incorporation of tannin-Ca complex. All the PVC formulations with tannins-Ca complex show excellent viscoelastic properties which were found to be slightly best or much closed to those obtained for PVC stabilized with commercial thermal stabilization.
文摘The influences ofphosphite and epoxy soybean oil in combination with liquid calcium/zinc isocaprylates on the thermal stability of flexible poly （vinyl chloride） were studied. The stabilizing effect of poly （vinyl chloride） was evaluated by Congo red method, thermoaging test and Thermogravimetric-differential Scanning Calorimetry （TG-DSC）. The results showed that the addition of the phosphite or epoxy soybean oil improved the thermal stability of PVC with the calcium/zinc isocaprylates stabilizing system, especially epoxidied soybean oil exhibited a remarkable effect, and the synergism on PVC thermal stability for 3：2 phenyl dioctyl phosphite to epoxidized soybean oil weight ratio was acquired. Accordingly, the rapid mass loss in TG curve occured between 258.9 ℃ and 334.4 ℃, which corresponded to the enthalpy of the pyrogenation of 609.2 J/g. It was also found that the stabilized PVC of the best ratio gave better mechanical and processing properties.
文摘介绍了CZ-900A型Ca/Zn复合热稳定剂在PVC制品中的应用效果,报道了其热稳定性能、流变性能和环保性能,并与目前国内同类产品进行了比较。试验结果表明:CZ-900A型Ca/Zn复合热稳定剂可以抑制Z n C l2对PVC的催化降解和"锌烧",具有较优的静态热稳定性、动态热稳定性和流变性能,且产品不含铅、镉等重金属,是新一代绿色环保型热稳定剂。
文摘： The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the thermal decomposition process,Mg-Al-CO3 hydrotalcite exhibits two steps- desorption of interlayer water occurs at 200℃ ,followed by dehydroxylation of the brucite-like layers and loss of carbonate at 400℃ ,Zn-Al-CO3 hydrotalcite decomposes in one step-the desorption of interlayer water, structural water and carbon dioxide occurred at the same time at 200℃ . The results of a theoretical study indicate that the bond strengths of OH-CO3-OH and OH-H2O-CO3-OH in Mg-Al-CO3 hydrotalcite are stronger than those in Zn-Al-CO3 hydrotalcite.It has been shown that the thermal stability of Mg-Al-CO3 hydrotalcite is higher than that of Zn-Al-CO3 hydrotalcite.
