Special Topics Review
Research progress on eugenol-based epoxy resin
Sun Xiaowei1, Li Liang1,2, Liu Kai 2,3, Yao Yongtao4, Cheng Yueran2,
Xie Yueyuan2, Shi Huiyun2, Zhang Yu2, Liu Shuai2
（1. School of Materials Science and Engineering, Shenyang Jianzhu University, Shenyang 110168, Liaoning, China; 2. Key Laboratory of Hebei Province on Vehicle Engineering Structural-Functional Integration, Tangshan Research Institute, Beijing Institute of Technology, Tangshan 063000, Hebei, China; 3. School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China; 4. School of Astronautics, Harbin Institute of Technology, Harbin 150006, Heilongjiang, China）
【Abstract】Eugenol, as a renewable natural phenolic compound, had become an important precursor for bio-based epoxy resin due to its abundant reactive groups in molecular structure. The preparation methods of eugenol-based epoxy resin were reviewed in this paper, providing a detailed analysis of functionalization strategies with phenolic hydroxyl groups, allyl groups, aromatic rings, and other structural units as derivatization sites, as well as their impact on resin performance. In addition, the latest research progress on thermal stability, flame retardant properties, mechanical properties, self-healing properties, dielectric properties, and degradability of eugenol-based epoxy resin was summarized. The application potential and challenges of this material in coatings, electronic packaging materials, composite materials, and adhesive were also explored.
【Keywords】epoxy resin; eugenol; organic synthesis; resin modification; green chemistry
Research Report
Ultrasonic exfoliation and functionalization modification of hexagonal boron nitride and
its application in polyacrylate pressure sensitive adhesive
Zhao Haichuan1, Mi Yongzhen2, Liu Kai3, Qu Xiongwei4
[1. Kemibond Advanced Materials (Tianjin) Co., Ltd., Tianjin 300383, China; 2.Hebei Provincial Engineering Machinery Rubber and Plastic Hose Technology Innovation Center, Hengshui 053200, Hebei, China; 3.Hebei Provincial Polyolefin Composite Pipe Technology Innovation Center, Langfang 065800, Hebei; 4.Hebei Key Laboratory of Functional Polymers, School of Chemical Engineering and Science, Hebei University of Technology, Tianjin 300401, China]
【Abstract】Hexagonal boron nitride (h-BN) is widely used as a filler to improve the thermal conductivity of polymers due to its high thermal conductivity, electrical insulation, and chemical stability. However, the small lateral size and poor compatibility limit the performance and application of h-BN in thermal management. In this paper, functionalized boron nitride nanosheets (f-BNNSs) were prepared by liquid-phase ultrasonic exfoliation and functionalization modification using silane coupling agent KH-560. Using it as a thermal conductive filler, polyacrylate pressure sensitive adhesive composite materials (f-BNNSs/PSAs) were successfully prepared by UV induced and bulk polymerization method. The research results showed that, ⑴ The dispersibility and interfacial bonding of f-BNNSs in the matrix were significantly improved after modification, and the exfoliation and modification processes effectively reduced the number of layers and stacking of boron nitride. ⑵ As the filling amount of f-BNNSs increased, the thermal conductivity of the composite material was significantly improved. When the mass fraction of the filler was 25%, the thermal conductivity reached 0.438 2 W/(m·K), which was nearly 150% higher than pure PSAs, and exhibited a lower percolation threshold (about 5%) and better heat dissipation efficiency. ⑶ The introduction of f-BNNSs significantly improved the 180° peel strength of the composite pressure sensitive adhesive while maintaining a moderate initial tack. This was attributed to the crosslinking effect between the functional groups on the surface of f-BNNSs and the polymer molecular chains, the enhancement effect brought by their high specific surface area, and the good dispersibility in the matrix. In summary, this study improved the thermal conductivity of pressure sensitive adhesive while maintaining and optimizing their core adhesion properties through structural design and surface functionalization, providing an effective method for developing high-performance thermally conductive pressure sensitive adhesive materials for electronic thermal management.
【Keywords】hexagonal boron nitride nanosheets; ultrasonic exfoliation; functionalization modification; thermal conductivity; pressure sensitive adhesive
Preparation and application of high-strength and heat-resistant polyester-based adhesive
for photovoltaic backsheet
Liu Leihao1,2, Chen Jianqing1, Liu Xin1, Jiang Ran1,3, Fu Xiaolong1,2,
Cai Jiannan2, Yang Donghui1,3, Jiang Jinghua1, Ma Aibin1
(1. College of Materials Science and Engineering, Hohai University, Jiangsu Provincial Engineering Research Center of Structure-Function Integrated Metallic Materials for Harsh Environments, Innovation Support Center for Critical Materials in Water Engineering Safety and Water Environment Management, Changzhou 213200, Jiangsu, China; 2. Changshu Friends Connector Technology Co., Ltd., Changshu 215500, Jiangsu, China; 3. Suqian Research Institute of Hohai University, Suqian 223814, Jiangsu, China;)
【Abstract】Aiming to address the problems of high melt viscosity, difficult processing, and insufficient heat and water resistance of polyester adhesive, modifications were made to the polyester by using acrylic resin, dibutyl phthalate (DBP), dibutyltin dilaurate (DBTDL), and hexamethylene diisocyanate (HDI). The effect of modifier content on the bonding strength of polyester adhesive was studied, and the optimal formula for modified polyester adhesive was determined. The photovoltaic backsheet adhesive was prepared by using this formula for backsheet lamination, and the heat resistance, chemical reagent resistance, and water resistance of the modified adhesive were studied. The research results showed that, the optimal formula for modified polyester adhesive was determined through single factor experiment and orthogonal experiment as follows: m(polyester):m(HDI)=20:1.0, the amount of acrylic resin added was 25% of the polyester mass, DBP was 7% of the acrylic resin mass, and DBTDL was 6% of the acrylic resin mass. The synergistic modification of HDI, acrylic resin, DBP, and DBTDL could significantly improve the peel strength, thermal stability, chemical reagent resistance, and water resistance of polyester adhesive. This adhesive was suitable for fields such as photovoltaic backsheet that required long-term outdoor exposure.
【Keywords】polyester adhesive; peel strength; heat resistance; chemical reagent resistance; water resistance
Study on the properties of waterborne polyurethane adhesive for automotive interior decoration prepared from different aliphatic diols
Yang Jun1, Chen Dengyu2, Wang Ziping2, Duan Mengting2,
Liu Bin2, Wang Xiaoping2, Jiang Bangzheng1, Zhu Shuzhen2
(1. Nantong Comens New Materials Co., Ltd., Nantong 226407, Jiangsu, China; 2. Beijing Comens New Materials Co., Ltd., Beijing 102502, China)
【Abstract】Using different types of aliphatic diols, hexamethylene diisocyanate (HDI), and isophorone diisocyanate (IPDI) as the main raw materials, diethylene glycol (DEG) as the small molecule chain extender, 2,2-dihydroxymethylpropionic acid (DMPA) and hydroxysulfonate (BY3306) as hydrophilic chain extenders, and ethylenediamine (EDA) as the post-chain extender, a series of waterborne polyurethane dispersion products with a solid content of 40% were synthesized by the acetone method in this study. The adhesive for automotive interior decoration was prepared by using the aforementioned dispersion as the main raw material, and the effect of different structured aliphatic diols on the bonding properties of waterborne polyurethane adhesive for interior decoration was systematically studied. The research results showed that, ⑴ The waterborne polyurethane dispersion with the target structure was successfully synthesized by using different aliphatic diols (PNA, PHA, PCDL, PBA, PTMEG). ⑵ All dispersion samples began to decompose at around 290-300 ℃, with good thermal stability. Among them, PBA, PHA, and PNA-based samples showed better thermal stability, while PCDL had relatively poor thermal stability. ⑶ The average particle size of all dispersions was below 600 nm, with good storage stability, meeting the basic requirements for subsequent research and application. The PBA-based dispersion had the smallest average particle size (about 204 nm) and exhibited excellent dispersibility. ⑷ In the peel strength test, PBA and PHA-based dispersions exhibited excellent bonding properties on PVC/PVC substrates, with significantly better initial and 72 h peel strength than other samples; On ABS/leather substrates, interior decoration adhesive prepared by PBA and PHA also exhibited excellent performance, with initial and 72 h peel strengths exceeding 20 N/2.5 cm. ⑸ In the heat resistance test, PBA-based sample showed the best heat resistance bonding performance (heat resistance for 8 minutes), followed by PNA-based sample (5 minutes), while PHA, PCDL, and PTMEG-based samples had relatively poor heat resistance. ⑹ Considering various properties, PBA-based waterborne polyurethane dispersion and interior decoration adhesive exhibited the most balanced performance in terms of dispersibility, bonding strength, and heat resistance, making them the preferred raw material system of adhesive applications for automotive interior decoration.
【Keywords】aliphatic diol; waterborne polyurethane; dispersion; interior decoration adhesive
Development and curing kinetics study of a novel epoxy adhesive containing triazine ring
Yang Hong, Duan Qiongming, Yu Xinhai
(College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China)
【Abstract】Using a multifunctional epoxy resin containing triazine ring and bisphenol A type epoxy resin as the main raw materials, adding organic silicone epoxy toughening agent, reactive diluent, epoxy chain extender, curing agent, and curing accelerator, an epoxy adhesive with excellent comprehensive performance was developed, and its various properties were tested and analyzed. The research results showed, the viscosity of the adhesive was significantly reduced at 50-70 ℃, and the gel time was shortened with the increase of temperature, so the adhesive had good processability. The tensile shear strength remained above 13.0 MPa within a wide temperature range of -60 to 110 ℃, and the mechanical properties were stable. Simultaneously using Kissinger and Crane equations, the apparent activation energy of the curing reaction was calculated to be 67.03 kJ/mol, with the reaction order of 0.9, and the curing process was controllable. In the frequency range of 100-1 000 kHz, the capacitance value remained stable at 4.46-4.56 pF, with the dielectric loss of 1.1%-1.6% and the relative dielectric constant of 3.44-3.52, exhibiting excellent frequency stability and low dielectric loss characteristics. The water absorption rate was only 0.09%, and it had good hydrophobicity. This adhesive had good processability, excellent mechanical properties, outstanding dielectric properties, and low water absorption over a wide temperature range, and had good application prospects in high-performance electronic packaging, high-frequency circuit insulation, and other fields.
【Keywords】triazine ring; epoxy resin; adhesive; curing kinetics
Process and Application
Study on waterborne adhesive with long open time for PVC floor
Zheng Yanqiu, Wang Depeng, Kuang Guangji, Xia Lingming, Zang Rui, Yang Meng
(Gleihow New Materials Co., Ltd., Fushun 113004, Liaoning, China)
【Abstract】In this study, a waterborne adhesive with long open time for PVC floor was successfully prepared by using a composite system of styrene-acrylic emulsion and VAE emulsion as the matrix, and adding components such as polyvinyl alcohol, rosin tackifying solution, heavy calcium carbonate, and glycerol. The effects of the type and amount of emulsion, the type and amount of polyvinyl alcohol, the amount of rosin tackifying solution, the type of heavy calcium, and the type and amount of humectant on the open time were mainly investigated. The research results showed that, ⑴ Selecting a styrene-acrylic emulsion with a glass transition temperature of -11 ℃ and adding 20% (mass fraction, the same below) of VAE emulsion for compounding could impart relatively good adhesion and strength to the adhesive solution, with an open time of up to 6 h. ⑵ When BP17 was selected as the polyvinyl alcohol and the addition amount was 6%, the open time of the adhesive solution could be up to 6 h. ⑶ The rosin tackifying solution made the adhesive easier to spread and penetrate on the substrate surface, increasing the contact area between the adhesive and the substrate, thereby improving the open time of the adhesive, and the relatively optimal addition amount was 20%. ⑷ Increasing the amount of heavy calcium carbonate powder would enhance the strength of the adhesive solution, but it would shorten the open time of the adhesive solution. Considering the cost of the adhesive solution, the ratio of heavy calcium carbonate [m(1 000 mesh)∶m(325 mesh)=2∶1] was selected, and when the addition amount was 16%, the comprehensive performance of the adhesive solution was optimal. (5) Glycerol exhibited strong intermolecular interactions and good compatibility. When its addition amount reached 4%, the open time of the adhesive solution could reach 6 h. The prepared adhesive had good bonding performance while significantly extending the opening time.
【Keywords】adhesive for PVC floor; long open time
Development and performance of epoxy injection adhesive for wet cracks in concrete
Hou Fujin1, Song Jiangpeng2, Liu Qingyang3, Zhang Wenwu1,
Wang Shanshan1, Zhang Shouqi2, Wang Youping3
(1. Expressway Operation Center, Shandong Hi-Speed Group Co., Ltd., Ji’nan 250098, Shandong, China; 2. Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure, China-Road Transportation Verification & Inspection Hi-Tech Co., Ltd., Beijing 100088, China; 3. Hainan Jiaokong Highway Engineering Maintenance Co., Ltd., Haikou 570203, Hainan China)
【Abstract】To address the limitations of conventional epoxy injection adhesive for repairing wet cracks in concrete, a series of epoxy injection adhesive were prepared in this study by compounding different hydrophilic epoxy resins and curing agents and introducing moisture-curing ketimine, and systematic research was then conducted. The research results showed that when the hydrophilic content was 25% and the ketimine content in component B was 40%, the new epoxy injection adhesive for wet cracks had both hydrophilicity and hydrophobicity, and the synergistic effect of them was optimal, meeting the technical requirements of GB 50728—2011 for concrete crack repair adhesive.It could effectively repair the four types of wet cracks (dry cracks, moistening cracks, wet cracks, and water-filled cracks) specified in the European standard EN 12618-2:2004. Its long term durability could be further studied to expand complex engineering applications.
【Keywords】epoxy injection adhesive; wet crack; ketimine; hydrophilicity
Study on low-viscosity anti-settling two-component thermal-conductive silicone potting adhesive
Huang Dakai, Chen Jianfeng, Chen Weijian, Yang Bin, Zhang Xiaoli, Yang Ying, Hu Yu
(Guangdong Pustar Materials Technology Co., Ltd., Dongguan 523651, Guangdong, China)
【Abstract】Using crystalline silicon micro powder, heavy calcium carbonate, and aluminum hydroxide as thermal conductive fillers, double-ended vinyl polydimethylsiloxane as the base silicone oil, hydrogen containing silicone oil as the crosslinking agent, α,ω-dihydroxypolydimethylsiloxane (107 adhesive) as the anti-settling agent, platinum catalyst as the vulcanizing agent, and 1-ethynyl-1-cyclohexanol as the inhibitor, two-component thermal-conductive silicone potting adhesive was prepared in this article. The effects of the type, particle size, ratio of the fillers, as well as the viscosity and addition amount of 107 adhesive on key properties such as viscosity, tensile strength, thermal conductivity, settling characteristics, and flame retardant grade of the potting adhesive were systematically studied. The research results showed that, by using a mixture of 5 μm crystalline silicon micro powder and 40 μm spherical aluminum hydroxide (with a mass ratio of 15:51 between spherical aluminum hydroxide and crystalline silicon micro powder), and adding a mass fraction of 1.0% of 107 adhesive, potting adhesive system could be obtained with excellent comprehensive performance such as the flame-retardant grade of V0, the settling mass of less than 2.70 g, the viscosity of about 2 000 mPa·s. This could effectively improve the settling and agglomeration defects of potting adhesive, providing effective reference for the development of related products.
【Keywords】two-component; silicone; thermal-conductive potting adhesive; anti-settling
Material Science
Synthesis of piperylene-modified dicyclopentadiene hydrogenated petroleum resin and its application in hot melt pressure sensitive adhesive
Chi Shuhui, Zou Hao, Bai Xiang, Li Yuqin, Xiang Zhenfen
(Ningbo Jinhai Chenguang Chemical Corporation, Ningbo 315207, Zhejiang, China)
【Abstract】In order to improve the performance of dicyclopentadiene (DCPD) hydrogenated petroleum resin and expanded its application, piperylene-modified DCPD hydrogenated petroleum resin was prepared through thermal polymerization and autoclave hydrogenation processes by using DCPD as the base raw material and piperylene as the modifying monomer. Then, hot melt pressure sensitive adhesive was prepared by mixing it with elastomer SIS and naphthenic oil, and its application performance in hot melt pressure sensitive adhesive was systematically evaluated. The research results showed that, ⑴ Nuclear magnetic hydrogen resonance and differential scanning calorimetry analysis confirmed that piperylene had been copolymerized into the molecular chain of DCPD hydrogenated petroleum resin, which improved the flexibility of the molecular chain while having no significant effect on the glass transition temperature. ⑵ During the polymerization process, increasing the amount of piperylene required extending the reaction time to maintain the stability of the resin’s softening point. Its straight-chain structure could effectively inhibit the crosslinking of molecular chain caused by DCPD, significantly reducing the content of insoluble substances in the product. ⑶ The introduction of piperylene improved the hydrogenation activity of the resin. The modified hydrogenation resin exhibited lower chroma and superior thermo-oxidative aging performance, with the aging chroma decreasing from 4.3 to 2.9. ⑷ In the application of hot melt pressure sensitive adhesive, the addition of piperylene could significantly improve the loop tack and 180° peel strength, with minimal impact on the holding power. Considering both the yield and comprehensive application performance of DCPD hydrogenated petroleum resin, it was recommended to control the amount of piperylene added at around 20% (mass fraction).
【Keywords】dicyclopentadiene; piperylene; petroleum resin; polymerization; hydrogenation; modification; mixing