Special Topics Review
Research progress on waterborne polyurethane acrylate resin and its modification
Liu Xueyan1, Han Lu2, Xia Lianghong1, Wang Chengqian3, Kan Chengyou2
(1.China Ordnance Industrial Standardization Research Institute, Beijing 100089, China; 2.Department of Chemical Engineering, Tsinghua University, Beijing 100084, China; 3.AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China)
【Abstract】Waterborne polyurethane acrylate (WPUA) has gained significant attention due to its excellent mechanical properties, high adhesion, chemical resistance, and environmental friendliness, leading to its widespread use in fields such as coatings, adhesive, textile and leather additives. In order to expand the application fields of WPUA, improving the performance of traditional WPUA through different approaches has become a research hotspot in the field of green waterborne resins in recent years. The current preparation methods of WPUA were first introduced in this paper, then the research progress of WPUA from the hot directions, including epoxy resin, organosilicone, organofluorine and nanoparticle modification of WPUA, as well as hyperbranched and photocurable WPUA was reviewed. Finally, the development directions of WPUA were put forward.
【Keywords】waterborne polyurethane acrylate; preparation method; modification; hyperbranched; photocurable
Research progress on bonding performance of concrete interfaces
Gao Teng1, Zhang Jin1, Wang Yun1
(School of Civil Engineering and Architecture, Shaanxi Sci-Tech University, Hanzhong 723001, Shaanxi, China )
【Abstract】Concrete repair technology has been widely applied in building reinforcement and repair, among which the bonding performance at the interface between new and old concrete has a significant impact on the effect after repair. The factors affecting the bonding performance of concrete interfaces, such as roughness, interface agent, and interface treatment methods were analyzed and discussed in this paper. Three commonly used testing methods of tensile test, shear test, and splitting tensile test were introduced, and some improvement methods for the shortcomings in traditional tests were listed. Finally, the future development of the bonding performance of concrete interfaces was discussed.
【Keywords】concrete repair; bonding performance; interface treatment method; roughness; interface agent; test method
Research progress on modification of waterborne acrylate adhesive
Fan Xiuming, Wang Xin, Jiang Hongyu
（Jilin Agricultural Science and Technology University, Jilin 132101, Jilin, China）
【Abstract】The development, classification, performance, and modification technology of acrylate adhesive were introduced. The main modification research of waterborne acrylate adhesive, with a particular focus on the modification of waterborne acrylate adhesive by using silicone and fluorine-containing monomers was summarized. The structural characteristics and performance changes of the modified products were analyzed in details. Finally, the development prospects of waterborne acrylate adhesive were discussed.
【Keywords】waterborne acrylate; adhesive; silicone; fluorine-containing monomer; modification
Research Report
Study on surface modification of ultra-high molecular weight polyethylene fiber and its composite bonding properties with waterborne polyurethane
Zhang Hong1, Wang Gui2, Li Xiaoming1, Li Jiahui1, Xing Lingxin1, Pei Kemei2
(1.Zhejiang Litai Composite Materials Co., Ltd., Deqing 313200, Zhejiang, China; 2.School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, Zhejiang, China)
【Abstract】Surface modification treatment of fibers is an important method to solve the problems of low surface activity and bonding properties of ultra-high molecular weight polyethylene (UHMWPE) fibers. In order to overcome the limitations of single modification method, liquid-phase oxidation methods (potassium permanganate method, sodium hydroxide method, and hydrogen peroxide method), plasma treatment method, and the combination of both to modify the surface of UHMWPE fiber cloth were adopted in this study. The surface molecular structure characteristics, appearance morphology, and bonding properties of fibers with waterborne polyurethane resin before and after modification were investigated. The research results showed that, ⑴ By comparing the peak load and 180° peel strength of different liquid-phase oxidation treatments and different treatment time, it could be seen that the modification effect of potassium permanganate solution treatment for 24 hours was relatively the best (the highest 180° peel strength could reach 1.28 N/mm, and the highest peak load could reach 32.831 N). This could be confirmed by the significant enhancement of the related absorption peaks in the FT-IR spectra and the significant increase of surface roughness in the SEM images. ⑵ After plasma treatment of untreated UHMWPE fiber cloth samples, the highest 180° peel strength could reach 1.01 N/mm and the highest peak load could reach 26.439 N after 180 s plasma treatment modification, indicating that plasma treatment could significantly improve the surface bonding properties of UHMWPE fiber cloth. However, excessive treatment could lead to a decrease in surface bonding properties due to the formation of a dense cross-linked layer. ⑶ After co-treatment of potassium permanganate liquid-phase oxidation and plasma, the maximum 180° peel strength could reach 2.12 N/mm, and the peak load could reach 53.087 N. The peel strength after modification treatment increased by more than 4 times compared to before modification, and the peak load increased by nearly 4 times. After co-modification with potassium permanganate solution and plasma, the polar groups and roughness on the fiber surface were significantly increased, effectively improving the bonding properties between the fiber and waterborne polyurethane matrix.
【Keywords】ultra-high molecular weight polyethylene fiber; surface modification; waterborne polyurethane; bonding
Effects of epoxy resin toughening systems on thermal properties of adhesive
Zhao Ming1, Zhang Xue1, Sun Mingming1, Zhang Xugang1, Zhang Bin1, Li Jianhui1, Wang Lei1, Li Yunyang2
(1.Institute of Petrochemistry Heilongjiang Academy of Sciences, Harbin 150040, Heilongjiang, China; 2.Heilongjiang Jiaotou Zhuanglong New Energy Technology Co., Ltd., Harbin 150040, Heilongjiang, China)
【Abstract】The effects of carboxyl-terminated butadiene acrylonitrile rubber (CTBN) and core-shell rubber toughening agents on the curing reaction heat, glass transition temperature (Tg), expansion coefficient, and tensile shear strength of epoxy adhesive systems were compared and investigated in this paper. The research results showed that, both CTBN and core-shell rubber could reduce the curing reaction heat of epoxy resin adhesive systems. The peak temperature of curing reaction in CTBN system increased, while the peak temperature of curing reaction in core-shell rubber system changed little. The addition of CTBN and core-shell rubber both reduced the Tg of the adhesive system, with the CTBN system showing a greater decrease than the core-shell rubber system. The addition of CTBN and core-shell rubber both increased the expansion coefficient of the adhesive system (<Tg), with the CTBN system showing a greater increase than the core-shell rubber system. With the continuous increase of CTBN and core-shell rubber addition, the tensile shear strength showed a trend of first increasing and then decreasing.
【Keywords】epoxy resin ; adhesive; toughening system; thermal property
Preparation, curing and properties of gallic acid-glycidyl methacrylate antibacterial photosensitive monomer
Zhao Chenjing, Guo Tianfei, Sun Weijie, Hou Guixiang
(Tangshan Key Laboratory of Functional Polymer Materials, College of Materials Science and Engineering, North China University of Science and Technology, Tangshan 063210, Hebei, China)
【Abstract】Gallic acid-glycidyl methacrylate (GA-GMA) unsaturated photosensitive monomers were prepared by one-step method using gallic acid (GA) and glycidyl methacrylate (GMA) as raw materials, and the structure, antibacterial properties and curing kinetics of GA-GMA/triethylene glycol dimethacrylate (TEGDMA) system with a mass ratio of 1∶1 were studied. The research results showed that, ⑴ Infrared spectroscopy and nuclear magnetic hydrogen spectroscopy analysis indicated that the target product was successfully prepared, and when n(GA)∶n(GMA)=1∶3, the reaction between GA and GMA was relatively complete. At this point, the carboxyl group had completely reacted with GMA, but there existed residual hydroxyl groups. ⑵ The synthesized GA-GMA monomers all had good antibacterial properties, but the antibacterial effect deteriorated with the increase of GMA ratio. Considering the curing effect, GA-GMA monomer with a ratio of n(GA)∶ n(GMA)=1∶3 was selected as the matrix for the cured resin. ⑶ By detecting the conversion rate of double bonds in the reaction, it was found that the curing rate of the GA-GMA/TEGDMA copolymer system was 78% after 120 s of curing, and the curing rate did not change significantly with the increase of curing time. Therefore, the light curing time of 120 s was relatively optimal. ⑷ As the amount of silicon-containing monomer increased, the contact angle of the composite resin surface with water also increased. When the addition amount was 20%, the surface contact angle with water reached 96.0°, achieving hydrophobic effect, indicating that the addition of silicon-containing monomer was beneficial for improving the anti adhesion of the resin surface. ⑸ The antibacterial rate of composite resins with different proportions of silicon-containing monomers reached over 90%, indicating that the cured composite resin had good antibacterial properties and could achieve the expected antibacterial effect.
【Keywords】gallic acid; photosensitive monomer; antibacterial property; light curing
Process and Application
Preparation and performance study of a new environmentally friendly epoxy adhesive
Zhang Yi, Chen Hongyi, Yu Xinhai
(College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China)
【Abstract】A new environmentally friendly epoxy adhesive system was prepared by using bisphenol S epoxy resin (SRTEM-S50) and polysulfone resin (SE3940) as the main components, supplemented with E-51 epoxy resin, chain extender (D-248) and epoxy toughening agent (CB-100), as well as adjusting the ratio of SRTEM-S50 and CB-100. Then its viscosity, gelation time, electrical properties, mechanical properties and water absorption properties were characterized and analyzed. The research results showed that, ⑴ The viscosity of five different formulation adhesive systems was inversely proportional to temperature. As the temperature increased, the viscosity of each adhesive continuously decreased, but the overall viscosity was moderate. Its apparent activation energy ranged from 59 to 71 kJ/mol, indicating high reactivity and suitability for most application occasions. ⑵ With the increase of temperature, the gelation time of each formulation adhesive was significantly shortened. The proportion of epoxy toughening agent in formulation SJ-3 was the largest, so the gelation time was the longest. When the temperature exceeded 160 ℃, the gelation time of each formulation was generally short. ⑶ The capacitance of formulation SJ-5 was relatively low, with the dielectric loss of less than 2%, the relative dielectric constant between 4.0 and 4.2, and good electrical insulation. This indicated that the allocation of each group in the formulation was relatively reasonable and had excellent electrical properties, which could be applied to the field of electronic insulation. ⑷ Each formulation had good toughness and excellent impact performance. In formulation SJ-4, the ratio of m(SRTEM-S50) to m(CB-100) was 10:2, and the impact toughness of the cured product was relatively high, reaching 13.7 kJ/m2. The sulfone-containing epoxy adhesive of various formulations exhibited excellent tensile shear strength, strong cold resistance, and excellent mechanical stability between -60 to 130 ℃. ⑸ The water absorption rate of five different formulations of sulfone-containing epoxy adhesive was less than 0.25%, demonstrating excellent hydrophobicity.
【Keywords】bisphenol S epoxy resin; polysulfone resin; sulfone-containing epoxy adhesive; preparation; performance
Effect of atmospheric pressure air plasma treatment on the bonding performance of styrene butadiene rubber floor cloth
Yu Zhuangzhuang, Xu Zhibao, Wang Meng, Chen Junhong, Yin Chengze, Sun Shaolin
(Yantai Branch Co., Ltd., No.52 Institute of China North Industries Group, Yantai 264003, Shandong, China)
【Abstract】Surface modification of styrene butadiene rubber floor cloth was carried out by using atmospheric pressure air plasma treatment technology. The changes in surface physicochemical properties before and after plasma treatment were analyzed by using contact angle measuring instrument, infrared spectrometer, X-ray photoelectron spectrometer, scanning electron microscopy, and atomic force microscopy. Modified silane sealant was used to bond the surface of floor cloth before and after plasma modification, and the effect of plasma treatment on the bonding performance of styrene butadiene rubber floor cloth was studied by combining the bonding strength and failure morphology. The research results showed that, ⑴ After atmospheric pressure air plasma treatment, the 180° peel strength of styrene butadiene rubber floor cloth increased by 806%, and the joint failure morphology changed from interface adhesion failure to adhesive cohesive failure. After plasma treatment, the interface bonding force between the adhesive and the floor cloth surface was greater than the cohesive force of adhesive, so it preferentially cracked from the inside of adhesive under peeling force. ⑵ After atmospheric pressure air plasma treatment, the surface wettability of styrene butadiene rubber floor cloth was significantly improved, the water contact angle decreased from 97.0° to 45.0°, and the surface free energy increased from 15.2 mJ/mm2 to 53.1 mJ/mm2, with a significant increase in the polarity component of surface free energy. ⑶ After atmospheric pressure air plasma treatment, the C=O absorption peak appeared clearly in the infrared spectrum. In addition, the surface O/C ratio of styrene butadiene rubber floor cloth increased from 3.1% to 16.2%, and the relative content of polar oxygen-containing groups (C—O and C=O) on the surface increased from 3.6% to 19.7%, which was the main reason for the improvement of surface wettability and 180° peel strength. ⑷ Scanning electron microscopy observed slight etching on the surface of floor cloth after plasma treatment. Atomic force microscopy observed that the root mean square roughness Rq of floor cloth surface increased from 105 nm to 134 nm. The increase in surface roughness may also be one of the reasons for the improvement in bonding strength from the perspective of mechanical biting force.
【Keywords】styrene butadiene rubber floor cloth; atmospheric pressure air plasma treatment; surface modification; wettability; bonding performance
Material Science
Preparation and influencing factors of lithium base lubricating grease with high dropping point and low water washout amount
Tian Sumin1, Yang Junliu2, Xia Xiaochun3, Ma Tan1
(1.Shanghai Plastics Research Institute Co., Ltd., Shanghai 201702, China; 2.704 Research Institute of China State Shipbuilding Corporation Limited, Shanghai 200031, China; 3.The Third Military Representative Office of the Air Force Armament Department in Shanghai, Shanghai 200235, China)
【Abstract】Lithium base lubricating grease was prepared by the pre-saponification process in this paper. Lithium base lubricating grease with high dropping point and low water washout amount was obtained by using poly-α-olefin, alkyl naphthalene, and polyol ester as base oils, as well as adjusting the proportion of base oils and experimental conditions. The effects of the type and addition amount of thickeners, the type and polarity of base oils, the addition timing of zinc dialkyl dithiophosphate (ZDDP), and the refining time on the dropping point and water washout amount of lubricating grease were investigated. The research results showed that, using the pre-saponification process with a mixture of poly-α-olefin, alkyl naphthalene, and polyol ester as base oils, and a lithium soap content (mass fraction) of approximately 36.8%, refining at a temperature of 180-190 ℃ for 40-50 min, lubricating grease with the dropping point of 269 ℃ and the water washout amount of less than 1.0% could be prepared. The characteristics of this process were simple process, easy operation, accurate control of soap content, and good stability of product quality.
【Keywords】lubricating grease; base oil; synthetic ester; ZDDP; dropping point; water washout amount
Preparation of modified nano zinc oxide and its application in epoxy resin
Wang Lingling1, Chen Miao1, Zhang Zhixin1, Chen Xiaoyu1, Wang Jie1, Liu Ju2
[1.Covay (Henan) New Materials Technology Co., Ltd., Nanyang 474650, Henan, China; 2.SINO-SINA Building Materials Co., Ltd., Zhengzhou 450001, Henan, China)
【Abstract】Modified nano zinc oxide was prepared by the steam method, using silane coupling agent KBM-603 as modifier. The changes in hydrophobicity, microscopic morphology, and particle size distribution of nano zinc oxide before and after modification were emphatically studied. Then, 20% of modified nano zinc oxide was added to epoxy resin, and the changes in mechanical properties and UV resistance before and after its addition were investigated. The research results showed that, ⑴ By investigating the modification temperature and modification time, the optimal modification process for nano zinc oxide was that modification temperature of 110 ℃, modification time of 2 h. ⑵ By measuring the contact angle, transmission electron microscopy, and particle size distribution of nano zinc oxide before and after modification, it was found that silane coupling agent KBM-603 as modifier could transform nano zinc oxide from hydrophilic powder to hydrophobic powder, reducing the surface energy and breaking up agglomeration, which could better enhance its absorption and reflection of light. ⑶ Adding 20% of silane coupling agent KBM-603 to modify nano zinc oxide in epoxy resin could not only improve its mechanical properties, but also enhance its resistance to UV aging.
【Keywords】nano zinc oxide; silane coupling agent; modification; epoxy resin; UV resistance