Special Topics Review
Research progress of hot melt pressure sensitive adhesive
Liu Tong1, Zhang Junying2,Ma Jiefang1, Gao Jiangnan1, Xu Dan1, Cheng Jue2, Song Jiayun1
(1.Beijing Tianyu Aerospace New Material Technology Co., Ltd., Beijing 101407, China; 2.College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100020, China)
【Abstract】The research progress of SIS-based hot melt pressure sensitive adhesive and polyurethane hot melt pressure sensitive adhesive at home and abroad was reviewed in this study. The advantages and disadvantages, modification methods (such as polymerization modification, physical blending modification, chemical modification), and research and application fields (such as metal bonding, logistics labels, building waterproofing materials, and medical adhesives) of both were elaborated, and the future development directions of SIS-based hot melt pressure sensitive adhesive and polyurethane hot melt pressure sensitive adhesive were also discussed.
【Keywords】modified SIS; polyurethane; hot melt pressure sensitive adhesive
Research progress of polyimide-based high-temperature resistant adhesive
Feng Pengju, Tang Fuqiang, Li Jinghui, Wang Yanjun
(Guangzhou High-Tech Zone Institute for Energy Technology Co., Ltd., Guangzhou 510670, Guangdong, China)
【Abstract】Polyimide adhesive has outstanding high-temperature resistance, dimensional stability, physical and chemical stability, dielectric properties, and bonding properties, making it a type of adhesive with excellent comprehensive performance, and therefore receiving increasing attention. In this paper, the research progress of classic (thermoplastic, thermosetting) polyimide adhesive, polyimide adhesive with molecular structure modification (molecular main chain structure modification, end group structure modification), and blend modified polyimide adhesive from the perspective of molecular structure was mainly reviewed, and the future development trend of polyimide adhesive was prospected.
【Keywords】polyimide; adhesive; molecular structure modification
Research progress on toughening modified epoxy resin with liquid nitrile rubber
Meng Fanning1,Wang Tong2,Yi Jianjun1
(1.Research Institute of Lanzhou Petrochemical Co., Ltd., PetroChina, Lanzhou 730060, Gansu, China; 2.Synthetic Rubber Plant of Lanzhou Petrochemical Company, PetroChina, Lanzhou 730060, Gansu, China)
【Abstract】Epoxy resin has low cost, excellent performance, and a wide range of applications. Currently, researchers are mostly modifying its toughness to compensate for structural deficiencies and further expand its application range. Among them, toughening modified epoxy resin with liquid nitrile rubber is one of the most successful methods in application. In this article, the toughening mechanism of epoxy resin was briefly introduced, the research progress of various liquid nitrile rubbers, such as carboxyl terminated liquid nitrile (CTBN), hydroxyl terminated liquid nitrile (HTBN), random carboxyl terminated liquid nitrile (XNBR), liquid nitrile (LNBR), amino terminated liquid nitrile (ATBN) and epoxy terminated liquid nitrile (ETBN) in toughening epoxy resin in recent years was reviewed, and the research direction of toughening epoxy resin with liquid nitrile rubber was prospected.
【Keywords】liquid nitrile rubber; toughening; epoxy resin; progress
Research progress of solventless silicone-modified epoxy electronic adhesive
Hu Liangkai, Yu Xinhai
（College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China）
【Abstract】Epoxy resin has a wide range of applications in the field of electronics. Introducing silicone-based Si—O—Si into epoxy resin can improve its brittleness, hardness, and poor weather resistance. In this article, the modification methods and characterization methods of solventless silicone-modified epoxy electronic adhesive were reviewed, some research progress of silicone-modified epoxy resins at home and abroad, and their applications in the electronic field (such as potting adhesive, LED sealant, conductive adhesive, etc.) were introduced, and the future development direction of silicone-modified epoxy resin was prospected.
【Keywords】epoxy resin; electronic adhesive; silicone; modification
Research Report
Study on epoxy resin modified by boron-containing triallyl compounds
Yuan Zhigang1,2, Liu Bo1, Zhang Bin1, Sun Mingming1,
Zhang Xugang1, Xue Gang1, Song Caiyu1, Li Jianhui1, Wang Lei1
（1.Institute of Petrochemistry Heilongjiang Academy of Sciences, Harbin 150040, Heilongjiang, China; 2. College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, Heilongjiang, China）
【Abstract】A boron-containing triallyl compound (TABM) was designed and prepared by Schiff base synthesis reaction using boron-containing triamine (TAB) and vanillin derived alkene compounds (AM) as raw materials. A series of modified resins (E-51+TABM) were obtained by changing the addition amount of TABM. The structure, thermal stability, thermomechanical properties, tensile shear properties, flame retardancy and microscopic fracture morphology of the cured resin were characterized. The research results showed that, ⑴ The test results of infrared spectroscopy and nuclear magnetic hydrogen spectroscopy both indicated that the target product TABM was successfully prepared. ⑵ The research on thermal stability and thermomechanical properties showed that with the increase of TABM dosage, the storage modulus and residual carbon rate of cured epoxy resin also increased, but its glass transition temperature and crosslinking density decreased. This indicated that the addition of TABM could reduce the rigidity of the material and improve the toughness of epoxy resin. ⑶ After adding TABM, the tensile shear strength of epoxy resin was improved at both room temperature and 100 ℃. When 10 parts of TABM were added, the tensile shear strength increased by 25.5% at 25 ℃ and 37.5% at 100 ℃. ⑷ As the content of TABM in the resin increased, the limit oxygen index (LOI) value of the cured resin also increased, reaching its maximum value when the addition amount reached 20 parts, indicating that the addition of TABM effectively improved the flame retardancy of the cured resin. ⑸ The microscopic fracture morphology analysis showed that the fracture toughness of the blended resin (E-51+TABM) was improved.
【Keywords】copolymerization modification; epoxy resin; thermal stability; thermomechanical property; shear strength
Synthesis and curing properties of bisphenol A-type phthalonitrile resin
Ding Nanyang1,2, Yan Xinyue1,2, Zhang Xiao'a1,2, Zhang Junying1,2,Wang Chengzhong1,2
(1.College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China; 2.Key Laboratory of Carbon Fiber and Functional Polymers of Ministry of Education, Beijing 100029, China)
【Abstract】Bisphenol A-type phthalonitrile resin was synthesized by using bisphenol A and 4-nitrophthalic acid as raw materials. Then, the structure of the synthesized resin was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance hydrogen spectroscopy (1H-NMR). Transition metal salts, aromatic diamines, organic phenols, and other curing agents were screened by using bisphenol A-type phthalonitrile resin as the matrix. The curing behavior of ZnCl2, DBTDL, m-BAPS, DDM,4,4'-biphenol, and various composite curing agents on the resin was studied by differential scanning calorimeter (DSC). The research results showed that, ⑴ The target product, bisphenol A-type phthalimide resin monomer was successfully synthesized. ⑵ In the combination of composite curing agents, the inorganic metal salt/organic amine composite curing agent composed of ZnCl2 and DDM had higher curing reaction activity, followed by the inorganic metal salt/organic phenol composite curing agent composed of ZnCl2 and4,4'-biphenol, and the organic metal salt/organic phenol composite curing agent composed of DBTDL and 4,4'-biphenol. The organic metal salt/organic amine composite curing agent composed of DBTDL and DDM and the organic amine/organic phenol composite curing agent composed of DDM/4,4'-biphenolhad relatively weaker curing activity. ⑶ Comparing various representative catalysts, curing agents and their composite curing agents, transition metal salt catalysts and their composite curing agents represented by inorganic metal salts had the highest curing reaction activity, followed by organic amines, and organic phenols and their composite curing agents had relatively lower reaction activity.
【Keywords】phthalonitrile resin; synthesis; curing agent; curing property
Development and performance study of new bulletproof epoxy adhesive
Li Yadong, Wan Chuansong, Yu Xinhai
(College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China)
【Abstract】A series of solvent-free epoxy adhesive systems were developed by using two kinds of epoxy resin, bismaleimide, epoxy chain extender, curing agent, accelerator, and two kinds of toughening agent, and their properties were comprehensively studied. The research results showed that, ⑴ Among the four different formulations of bulletproof epoxy adhesive, JC-4 had a moderate viscosity and a uniform overall downward trend with increasing temperature. When the temperature reached 60 ℃ or above, the viscosity was within 400 mPa·s, which facilitated fiber coating. The four formulations of epoxy adhesive had high reactivity, and could be cured at room temperature without damaging the performance of UHMWPE fiber. ⑵ The four formulations of bulletproof epoxy adhesive showed excellent shear strength in the medium and low temperature range, among which the adhesive of JC-3 and JC-4 formulations exhibited superior shear strength of over 11 MPa at 120 ℃, demonstrating good high-temperature stability and meeting the basic requirements of resin based strength and heat resistance for bulletproof composite materials. ⑶ The relative dielectric constants of the four formulations were between 3.9 and 4.5, all of which had good dielectric properties. Among them, the epoxy adhesive prepared by JC-4 formulation had the lowest dielectric constant and good electrical insulation properties. The dielectric loss of JC-2, JC-3, and JC-4 was within 1.8%, demonstrating excellent stability in dielectric loss. The water absorption rate of the four formulations of epoxy adhesive ranged from 0.36% to 0.65%, all of which had excellent hydrophobic properties. Among them, the JC-4 formulation adhesive had the lowest water absorption rate of only 0.362%. ⑷ The JC-4 formulation was used as the adhesive for bulletproof composite materials. The bulletproof composite materials were not penetrated during the shooting test, and the back surface was raised by the impact of the bullet, with a height of 23 mm, which could meet the performance requirements of the adhesive for bulletproof composite materials.
【Keywords】heat-resistance; epoxy resin adhesive; bulletproof composite material; adhesive property
Process and Application
Preparation of hyperbranched waterborne photosensitive resin and its application in 3D printing
Wen Xinyu1, Yang Wenqiang1, Liu Jin1, Zhang Dongqi1, Luo Qinghong1, Liu Xiaoxuan1,2
(1.School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, Guangdong, China; 2.Guangdong Laboratory of Chemistry and Fine Chemical Industry Jieyang Center, Jieyang 522000, Guangdong, China)
【Abstract】A carboxyl terminated hyperbranched polyester (CHBP) was synthesized by using citric acid (CA) and neopentyl glycol (NPG), and then it was modified with glycidyl methacrylate (GMA) to prepare hyperbranched waterborne polyester acrylate (WCHBPA). Its structure was characterized by infrared and nuclear magnetic hydrogen spectroscopy. A washable 3D printed photosensitive resin was obtained through formula design, and the effects of the dosage and irradiation intensity of the photoinitiator (TPO-L) on the photopolymerization kinetics of the composite resin were investigated. In addition, the influence of the mass ratio of hyperbranched waterborne polyester acrylate and acryloylmethiolane (ACMO) on the mechanical properties, glass transition temperature, and thermal weight loss of 3D printed splines was also studied. The research results showed that, ⑴ The target products CHBP and WCHBPA were successfully prepared. ⑵ In this study, four types of 3D printing photosensitive resins with suitable viscosity were formulated, which could meet the basic requirements of 3D printing. Under the conditions of radiation intensity of 40 mW/cm2 and TPO-L dosage of 2.0% (mass fraction), the conversion rate of double bonds reached the highest. ⑶ As the content of diluent (ACMO) increased from 30% to 60%, the tensile strength of the cured sample gradually increased from 13.3 MPa to 45.6 MPa, the impact strength decreased from 2.98 kJ/m2 to 1.53 kJ/m2, and the glass transition temperature gradually increased from 92.4 ℃ to 151.1 ℃. ⑷ The parts obtained through 3D printing were clear and accurate, which had certain reference significance for the preparation of high-performance washable 3D printing photosensitive resins and formula design.
【Keywords】hyperbranched; polyester acrylate; waterborne; photosensitive resin ; UV curing; 3D printing
Evaluation of the reliability application of a high thermal conductivity insulating adhesive in the satellite-borne terminal machine
Zhang Sheng, Zhang Chenhui, Xu Peilun, Jin Xing, Liu Zhidan
(China Electronics Technology Group Corporation No.20th Research Institute, Xi'an 710068, Shaanxi, China)
【Abstract】In response to the reliability application requirements of high thermal conductivity insulating underfill adhesive for satellite-borne terminal machine, a comprehensive impact assessment on the reliability and environmental adaptability of two-component high thermal conductivity insulating adhesive was conducted. The intrinsic performance indicators and processability indicators were tested and verified through standard samples of thermal conductivity insulating adhesive performance testing, and their qualifications were analyzed and evaluated as well. Typical BGA daisy-chain network structure samples were designed and produced, and by using thermal conductive adhesive filling technology, the effect of void ratio of thermal conductivity insulating adhesive on BGA device solder joints was verified and its process adaptability was also evaluated. Satellite-borne terminal loading was designed and manufactured, and acceptance-level environmental and reliability tests on satellite-borne products were conducted, in order to verify that the terminal loading had the ability to withstand working and environmental stresses. This high thermal conductivity insulating adhesive met the requirements of heat dissipation and high load resistance for satellite-borne products, achieving reliable applications.
【Keywords】high thermal conductivity insulating adhesive; daisy-chain; solder joint; void rate; environmental test; reliability
Material Science
Preparation and performance study of secondary dispersion of chloroether-acrylic resin
Dong Qunfeng1, Niu Hongrang1, Liu Chuanqi1, Yang Lifeng1, Huang Yongjie2, Pei Kemei2
(1. Zhejiang Tiannu Group Paint Co., Ltd., Tongxiang 314505, Zhejiang, China; 2. School of Chemistry and Chemical Engineering, Zhejiang SCI-TECH University, Hangzhou 310018, Zhejiang, China）
【Abstract】The secondary dispersion of chloroether-acrylic resin was synthesized by solution polymerization method using chloroether resin as a modified resin. Then, the two-component water-based coating was prepared in a ratio of m(chlorinated ether-acrylic resin secondary dispersion) : m(amino resin curing agent)=5:1. The effects of solvent content, reaction temperature, neutralizer type and neutralization degree, and hydroxyl content on the secondary dispersion were explored. The molecular structure of the modified resin and the particle size of the dispersion were tested and characterized. The properties of chloroether-acrylic resin aqueous dispersion and its two-component baking coating were studied. The research results showed that, the optimized preparation conditions for chloroether resin modified acrylic resin solution were the reaction temperature of 90-100 ℃, the reaction time of 5 hours, solvents of propylene glycol butyl ether and 2-butoxyethanol (with the content of about 11% of the total mass of the aqueous dispersion), initiator of BPO, and HPA as crosslinking functional monomer. Under the optimal synthesis conditions, the chloroether resin modified acrylic ester aqueous dispersion was prepared. The modified aqueous dispersion had a milky white appearance with blue light, the solid content of about 48%, the viscosity of 3 015 mPa ? s, the average particle size of about 185 nm, and stable storage at (50±2) ℃/7 days. Compared with commercially available hydroxy acrylic acid aqueous dispersion, the coating film properties of the chloroether-acrylic resin dispersion prepared in this article were more superior.
【Keywords】chloroether resin; modification; acrylic resin; secondary dispersion; property