POLYMER DEGRADATION AND STABILITY
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2021
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IF 5.03
Dongyue Liu,Pengfei Ji,Tianlong Zhang,Jipeng Lv,Yihua Cui
A bi-DOPO type of prepolymer for flame retardancy epoxy resins with intrinsically flame-retardant was successfully synthesized by reacting of 6,6′-((6,6′-dihydroxy-[1,1′-biphenyl]-3,3′-diyl) bis (propane-3,1-diyl)) bis(dibenzo[c,e][1,2] oxaphosphinine 6-oxide) (DOBP) with bisphenol A. The characterization of the cured epoxy resins, such as cone calorimeter, TGA/infrared, Raman and SEM indicated that DOBP with double 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) structure endowed the epoxy resins with excellent flame retardancy, including limiting oxygen index of 40.0%, V-0 rating in UL-94, remarkable smoke suppression and flame inhibition. The quenching effect of gaseous phase and charring effect of condensed phase of phosphaphenanthrene groups in prepolymer together contributed to the improvement on the flame retardant performance of the epoxy resins. In addition, due to the rigid structure of DOBP molecules, the cured d -FREP possessed high glass transition temperature of up to 192.9°C, and the tensile modulus of which was increased about 55% compared with the neat epoxy resins.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2017
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IF 2.843
Yuan Cao,Xiu-Li Wang,Wen-Qiang Zhang,Xue-Wu Yin,Yue-Quan Shi,Yu-Zhong Wang
A novel reactive phosphorus-containing flame retardant 1,4-phenylene-bis((6-oxido-6H-dibenz[c,e][1,2]-oxaphosphorinyl) methylene) diacrylate (TDCAA-DOPO), with two symmetrical 9,10-dihydro-9-oxa-10-phosphaphena-nthrene-10-oxide structure (bi-DOPO), was synthesized and combined with unsaturated polyester resin (UPR) via cross-linking to prepare flame-retardant UPR (FR-UPR). To make clear both the effects of the bi-DOPO structure and the cross-linking reaction on the thermal stability and flame retardancy of UPR, an additive flame retardant that also owned bi-DOPO structure but without a vinyl bond, 1,4-phenylene-bis((6-oxido-6H-dibenz[c,e][1,2]-oxaphosphorinyl) carbinol) (TDCA-DOPO), was used as a contrast. The results showed that the incorporation of TDCAA-DOPO or TDCA-DOPO into UPR can reduce its peak heat release rate (PHRR) and total heat release (THR), as well as improve the limiting oxygen index (LOI) value. As compared to TDCA-DOPO, the reactive TDCAA-DOPO endowed FR-UPR with enhanced thermal stability, residual char, and glass transition temperature (Tg), which were even higher than those of pure UPR. Besides, their flame-retardant mechanism for UPR had been well investigated.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
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2021
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IF 9.078
Hao Wang,Jun Yuan,Zongmin Zhu,Xianze Yin,Yunxuan Weng,Zhaojia Wang,Feihua Yang,Jiayu Zhan,Hua Wang,Luoxin Wang
It is always a challenge to prepare multifunctional epoxy resins (EP) composites with excellent flame retardance, mechanical property and high transparency. In this work, a reactive flame-retardant (BDO) was synthesized from DOPO, 3,5-diamino-triazolz and thiophene-2-formaldehyde, and taken to prepare EP/BDO composites. Surprisingly, benefitting from the synergy of efficient flame retardant unit (DOPO structure), catalytic curing unit (triazole structure) and optical functional structure (thiophene-2-formaldehyde), the EP composites with excellent comprehensive performance was obtained. In detailed, after adding only 5 wt% BDO, the EP composites passed the UL-94 V-0 level, and the limiting oxygen index was increased to 33% from 22.5% of neat EP. At the same time, EP/BDO-5 showed obvious heat suppression and smoke suppression effects. Besides, EP/BDO-5 presented excellent mechanical strength , that the tensile strength and bending strength were increased by 25% and 30% compared with neat EP. Moreover, EP/BDO composites maintained the same good light transmittance as neat EP, and also presented enhanced T g and dielectric property . In addition, the dual phase flame-retardant mechanism was revealed through systematically analyzing residues after combustion and the gaseous phase products of flame retardant. The above results indicated EP/BDO composites with excellent comprehensive performance possessed a great potential application in high-performance composites fields.
研究领域:
材料科学
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高分子化学
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复合材料
✓ 已验证
产品关联
DOI
高影响因子