MATERIALS LETTERS
·
2014
·
IF 2.269
Xiaorui Zhang,Lizhu Liu,Jinfeng Li,Ling Weng,Weiwei Cui
TiO 2 –polyester composite emulsions with low contact angle on steel sheet were prepared in a “core-shell” structure employing ultrasonic irradiation. The cluster size of the TiO 2 was reduced and the nano-particles were well dispersed. The molecular weight of the polyester resin initially decreased, then increased forming the characteristic core-shell structure. This was a clear indication that the TiO 2 particles were coated with the recombined polyester as a direct result of the ultrasonic irradiation. The contact angle of the emulsion was reduced which indicated that the wettability of the emulsion was improved without the addition of chemical additives. These results suggest the possibility of producing low contact angle coatings by mechanical way.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2021
·Vol. 138
·期 34
·50853
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IF 3.125
Junzhi Ma,Dong Wang,Shaohai Fu
To improve flame-retardant properties of unsaturated polyester resin (UPR), two phosphorus-containing vinyl monomers with different chemical structures were synthesized to replace styrene molecules and then copolymerized with UPR oligomers to prepare flame-retardant phosphatized UPRs. Curing behavior of phosphatized UPRs was investigated by DSC non-isothermal curing curves, deducing the best curing conditions. Cone calorimeter results demonstrated the obvious reduction of heat release rate and smoke production rate by comparing phosphatized UPRs with flammable UPR. TG-IR-MS coupling technique was utilized to reveal thermal degradation and pyrolytic volatiles including aromatic compounds, hydrocarbons, CO, PO 4 ˙, and so forth, providing more information of smoke toxicity and the gas phase flame- retardant mechanism of phosphatized UPRs. Moreover, the yield, compactness and graphitic degree of char residues of phosphatized UPRs were increased, strengthening the barrier effect to inhibit the permeation of combustion heat and the effusion of pyrolytic volatiles in the condensed phase.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Zhenzeng Wu,John Tosin Aladejana,Shuqiong Liu,Xinhuai Gong,Xiaodong Alice Wang,Yongqun Xie
Unsaturated polyester resin (UPR) with good chemical resistance, excellent mechanical properties, and formaldehyde-free shows great potentials in the wood industry. In this study, the mechanical strength, thermostability, dynamic thermomechanical property, and interfacial bonding of bamboo particle boards (BPBs) made from UPR adhesives with toluene diisocyanate (TDI) as the coupling agent were explored. The results showed that covalent bonds were formed among TDI, bamboo particles, and UPR, which could significantly enhance the mechanical strength. The internal bonding strength, modulus of elasticity, and modulus of rupture of treated BPBs were 1.36, 3010, and 19.6 MPa with the increment of 1250, 514, and 833%, respectively, compared to the control samples. Also, the thickness swelling rate of the BPB was 4.6%, much lower than that of the control, with a decrease of 92%. The thermostability of the treated BPB was also improved. As a result, the BPB using UPR as the adhesive and TDI as the coupling agent shows better usability, higher efficiency, and excellent mechanical strength.
研究领域:
材料科学
·
林业工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 47
·
IF 1.768
Yi-Fan Zhang,Xiao-Jun Wang,Zhi-Gang Pan,Cheng-Ming Hong,Gao-Feng Ji
The activation of foaming agent is critical to its application. In this study, 4,4′-oxibis-(benzenesulfonyl hydrazide) (OBSH) activated by urea was used in the manufacture of low-density unsaturated polyester resin (LDUPR), and the results were compared with that of OBSH activated by zinc oxide and zinc stearate. The experiment results showed that the activation of OBSH by urea was better than by zinc oxide or by zinc stearate. A novel hydrogen bond activation mechanism of urea is presented in this research. Two stages, including the induction stage and the foaming stage, were proposed in the LDUPR manufacture according to the gas evolution curves of activated OBSH. The decomposition temperature and the decomposition time of OBSH activated by urea were determined to match the gelation time of UPR for the manufacture of LDUPR. The disadvantageous chemical behaviors of activated OBSH were eliminated in the induction treatment. The activated OBSH via induction treatment released gas maximally and distributed gas homogeneously in the resin glue, resulting in a better foaming effect than that of the previous foaming agents. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42824.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF REINFORCED PLASTICS AND COMPOSITES
·
2024
·
IF 2.3
Xinrui Wu,Qiong Lan,Junlong Yao,Yalan Tian,Susu Li,Zhitian Deng
To synchronously strength and plasticize unsaturated polyester resin (UPR), maleic anhydride were directly added in the unsaturated polyester resin solution and form the styrene-maleic anhydride oligomer (SMAO) without initiation. The creating SMAO cross link with UPR by curing reaction, and the prepared UPR resin exhibit higher tensile, elongation, bending strength and higher impact strength simultaneously, 0.45, 0.36, 0.76 and 0.12 times than UPR matrix, SMAO-UPR exhibits obvious plastic fracture characteristics; The DSC result indicates that the curing degree of SMAO-UPR is 96.55% which is 1.45% lower than that of UPR; The TG result indicates that MA and St mainly form an alternating copolymer below 90°C. The SEM and DMA result indicates that SMAO improves the morphology and structure which shows plastic deformation of UPR, and there is a certain interface effect between SMAO and UPR. Compared with the traditional method of large molecular weight SMA modified UPR, this method of reinforcing UPR is better for mechanical property, easy to operate, inexpensive, and highly applicable in industrial production.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION
·
2017
·
IF 0
Zhiquan Chen,Mengwei Jiang,Qingwu Zhang,Yuan Yu,Guangping Sun,Juncheng Jiang
A series of flame-retardant unsaturated polyester resin (UPR) were prepared by the addition of dimethyl methylphosphonate (DMMP) with various amounts of aluminum hydroxide (ATH) or ammonium polyphosphate (APP) as the flame retardants. The combustion resistance effects of ATH/DMMP and APP/DMMP systems were evaluated by limiting oxygen index test and vertical burning test (UL-94). The thermal properties of UPR were investigated by thermogravimetric analysis. The structure of char was observed by scanning electron microscopy. DMMP incorporated with ATH or APP improved the flame retardancy and thermal properties of UPR. However, the fire-retardant mechanism of these two systems were different: The ATH/DMMP system provided synergistic effect in charring property of the UPR, produced great amount of residual char, and thus revealed the excellent flame retardancy. The APP/DMMP system further improved the flame retardancy of the UPR due to the change in the residual char structure rather than the increase in the production of char.
研究领域:
高分子科学
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材料工程
·
消防安全工程
·
化学工程
✓ 已验证
DOI
危险品化学品经营许可证（带存储）