A stable epoxy emulsion was prepared with epoxy resin (EP) as raw material, 2-acrylamido-2- methyl-l-propanesulfonic acid (AMPS) as modifier and benzoyl peroxide as initiator. By criterion of yield of the copolyme...A stable epoxy emulsion was prepared with epoxy resin (EP) as raw material, 2-acrylamido-2- methyl-l-propanesulfonic acid (AMPS) as modifier and benzoyl peroxide as initiator. By criterion of yield of the copolymer AMPS-EP, water-solubility, change of the acid value and intrinsic viscosity [η] along with reaction time, the copolymerization course was deduced. It is found that during the process, AMPS takes part in both the grafting copolymerization with epoxy principal chain and the ring-opening polyaddition with epoxy group. It is also discovered that the yield of AMPS-EP and water dispersing varies with reaction time. When it reaches 1.5 h, AMPS-EP can obtain good water-solubility; but the water-solubility will go bad gradually if it exceeds 3.5 h.. R spectrum analysis indicates that partial epoxy group partially remains and the others create sulfonic ester.展开更多
Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high-temperature rutting test, low-temperature bending test and ...Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high-temperature rutting test, low-temperature bending test and controlled stress flexural fatigue test are used to study the performance of asphalt mixtures modified by epoxy resin including high-temperature stability, low-temperature cracking-resistance, and fatigue cracking-resistance, which are served to evaluate the modification effect of epoxy resin of different contents. With the addition of epoxy resin, all the three performances are improved greatly. However, when the amount of epoxy resin added is over a certain value, the modification effect will be stable with no extra benefit detected. Finally, in terms of the properties of the three respects, 20%, 30%, 30% are given separately as the proposal adding contents.展开更多
Good compatibility between waterborne epoxy resin(WER)modifier and styrene-butadiene rubber(SBR)latex modified asphalt emulsion(SBRE)is an essential premise for good pavement performance of WER and SBR latex composite...Good compatibility between waterborne epoxy resin(WER)modifier and styrene-butadiene rubber(SBR)latex modified asphalt emulsion(SBRE)is an essential premise for good pavement performance of WER and SBR latex compositely modified asphalt emulsion(WSAE).This study aims to explore the compatibility between WER modifier and SBRE.To achieve the goal,several WER modifiers produced by two methods were first selected to modify SBRE,thus the WSAEs were prepared.Next,storage stability and workability of the WSAEs themselves,and high-temperature performance,rheological behavior and temperature sensitivity of their evaporated residues were compared and evaluated via performing a series of experiments,respectively,thus the WER modifier possessing an optimal modification effect was recommended.Results show that the storage stability of WSAEs is sensitive to the amount of WERs.The incorporation of 1%WERs by the mass of SBRE improves the storage stability of SBRE,while WERs that exceed 1%weaken its storage stability.When the WERs reach 3%and 4%,the 5 d storage stability of prepared WSAEs will be beyond the limitation of specification.Incorporating WERs into SBRE negatively affects the workability of SBRE,and the workability of WSAEs is adversely influenced by the WERs content and the storage time.To ensure the construction,the WSAEs with 3%and 4%WERs should not be stored for more than 36 h and 48 h,respectively.The WERs effectively improve the high-temperature performance of SBRE residue,especially the 3%WERs.Besides,the WERs notably enhance the rheological property and thermal stability of SBRE residue.In contrast,the WER modifier produced by chemically modified method has a smaller adverse impact on the storage stability and workability of WSAE,and a larger enhancement on the high-temperature performance,rheological property and thermal stability of SBRE residue,which is thus recommended to modify SBRE.展开更多
Epoxy-based composites containing montmorillonite(MMT)modified by silylation reaction withγ-aminopropyltriethoxysilane(γ-APTES)and 3-(glycidyloxypropyl)trimethoxysilane(GPTMS)are successfully prepared.The effects of...Epoxy-based composites containing montmorillonite(MMT)modified by silylation reaction withγ-aminopropyltriethoxysilane(γ-APTES)and 3-(glycidyloxypropyl)trimethoxysilane(GPTMS)are successfully prepared.The effects of filler loading and surface modification on the electrical and thermal properties of the epoxy/MMT composites are investigated.Compared with the pure epoxy resin,the epoxy/MMT composite,whether MMT is surface-treated or not,shows low dielectric permittivity,low dielectric loss,and enhanced dielectric strength.The MMT in the epoxy/MMT composite also influences the thermal properties of the composite by improving the thermal conductivity and stability.Surface functionalization of MMT not only conduces to the better dispersion of the nanoparticles,but also significantly affects the electric and thermal properties of the hybrid by influencing the interfaces between MMT and epoxy resin.Improved interfaces are good for enhancing the electric and thermal properties of nanocomposites.What is more,the MMT modified with GPTMS rather thanγ-APTES is found to have greater influence on improving the interface between the MMT filler and polymer matrices,thus resulting in lower dielectric loss,lower electric conductivity,higher breakdown strength,lower thermal conductivity,and higher thermal stability.展开更多
文摘A stable epoxy emulsion was prepared with epoxy resin (EP) as raw material, 2-acrylamido-2- methyl-l-propanesulfonic acid (AMPS) as modifier and benzoyl peroxide as initiator. By criterion of yield of the copolymer AMPS-EP, water-solubility, change of the acid value and intrinsic viscosity [η] along with reaction time, the copolymerization course was deduced. It is found that during the process, AMPS takes part in both the grafting copolymerization with epoxy principal chain and the ring-opening polyaddition with epoxy group. It is also discovered that the yield of AMPS-EP and water dispersing varies with reaction time. When it reaches 1.5 h, AMPS-EP can obtain good water-solubility; but the water-solubility will go bad gradually if it exceeds 3.5 h.. R spectrum analysis indicates that partial epoxy group partially remains and the others create sulfonic ester.
文摘Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high-temperature rutting test, low-temperature bending test and controlled stress flexural fatigue test are used to study the performance of asphalt mixtures modified by epoxy resin including high-temperature stability, low-temperature cracking-resistance, and fatigue cracking-resistance, which are served to evaluate the modification effect of epoxy resin of different contents. With the addition of epoxy resin, all the three performances are improved greatly. However, when the amount of epoxy resin added is over a certain value, the modification effect will be stable with no extra benefit detected. Finally, in terms of the properties of the three respects, 20%, 30%, 30% are given separately as the proposal adding contents.
基金funded by the National Natural Science Foundation of China(NSFC)under Grant No.211021180360the Transportation Science and Technology in Shaanxi Province under Grant No.KY17-02.
文摘Good compatibility between waterborne epoxy resin(WER)modifier and styrene-butadiene rubber(SBR)latex modified asphalt emulsion(SBRE)is an essential premise for good pavement performance of WER and SBR latex compositely modified asphalt emulsion(WSAE).This study aims to explore the compatibility between WER modifier and SBRE.To achieve the goal,several WER modifiers produced by two methods were first selected to modify SBRE,thus the WSAEs were prepared.Next,storage stability and workability of the WSAEs themselves,and high-temperature performance,rheological behavior and temperature sensitivity of their evaporated residues were compared and evaluated via performing a series of experiments,respectively,thus the WER modifier possessing an optimal modification effect was recommended.Results show that the storage stability of WSAEs is sensitive to the amount of WERs.The incorporation of 1%WERs by the mass of SBRE improves the storage stability of SBRE,while WERs that exceed 1%weaken its storage stability.When the WERs reach 3%and 4%,the 5 d storage stability of prepared WSAEs will be beyond the limitation of specification.Incorporating WERs into SBRE negatively affects the workability of SBRE,and the workability of WSAEs is adversely influenced by the WERs content and the storage time.To ensure the construction,the WSAEs with 3%and 4%WERs should not be stored for more than 36 h and 48 h,respectively.The WERs effectively improve the high-temperature performance of SBRE residue,especially the 3%WERs.Besides,the WERs notably enhance the rheological property and thermal stability of SBRE residue.In contrast,the WER modifier produced by chemically modified method has a smaller adverse impact on the storage stability and workability of WSAE,and a larger enhancement on the high-temperature performance,rheological property and thermal stability of SBRE residue,which is thus recommended to modify SBRE.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21806129,51872238,51407134,and 51521065)the China Postdoctoral Science Foundation(Grant No.2016M590619)+3 种基金the Natural Science Foundation of Shandong Province,China(Grant No.ZR2016EEQ28)the State Key Laboratory of Electrical Insulation and Power Equipment,China(Grant No.EIPE14107)the Fundamental Research Funds for the Central Universities,China(Grant No.3102018zy045)the Natural Science Basic Research Plan in Shaanxi Province,China(Grant No.2017JQ5116)
文摘Epoxy-based composites containing montmorillonite(MMT)modified by silylation reaction withγ-aminopropyltriethoxysilane(γ-APTES)and 3-(glycidyloxypropyl)trimethoxysilane(GPTMS)are successfully prepared.The effects of filler loading and surface modification on the electrical and thermal properties of the epoxy/MMT composites are investigated.Compared with the pure epoxy resin,the epoxy/MMT composite,whether MMT is surface-treated or not,shows low dielectric permittivity,low dielectric loss,and enhanced dielectric strength.The MMT in the epoxy/MMT composite also influences the thermal properties of the composite by improving the thermal conductivity and stability.Surface functionalization of MMT not only conduces to the better dispersion of the nanoparticles,but also significantly affects the electric and thermal properties of the hybrid by influencing the interfaces between MMT and epoxy resin.Improved interfaces are good for enhancing the electric and thermal properties of nanocomposites.What is more,the MMT modified with GPTMS rather thanγ-APTES is found to have greater influence on improving the interface between the MMT filler and polymer matrices,thus resulting in lower dielectric loss,lower electric conductivity,higher breakdown strength,lower thermal conductivity,and higher thermal stability.
文摘为了提高丙烯酸树脂的耐水性、附着力以及耐溶剂性,以桐油酸和环氧树脂E-44为原料制备环氧酯,采用溶液聚合和自乳化工艺合成了环氧酯改性水性丙烯酸树脂,并引入氰特CY325氨基树脂制备双组分环氧酯改性水性丙烯酸树脂漆膜。利用FT-IR、1 H NMR、粒径测试等对环氧酯单体、环氧酯改性水性丙烯酸树脂的结构和性能进行表征和分析,并测试了单组分和双组分环氧酯改性水性丙烯酸树脂漆膜的硬度、光泽、吸水率、水接触角、耐溶剂性等性能。结果表明:当环氧酯用量为35%时,单/双组分漆膜综合性能达到最佳,双组分漆膜光泽(60°)达102.3,耐溶剂擦拭次数为500次,耐水性可达480 h,附着力为0级,铅笔硬度为4H,耐冲击性为50 cm。