INDUSTRIAL CROPS AND PRODUCTS
·
2021
·
IF 5.645
Rong Yang,Mengdi Li,Xin Zhang,Jinchun Li
Bio-based polyols (MCPs) were synthesized from 1,6-hexanediol, malic acid , and citric acid by a series of one-pot esterification reactions. Subsequently, water-blown rigid polyurethane foams (RPUF) were prepared using the MCPs and polyisocyanates by a catalyst-free method. The effect of the molar ratios of malic acid to citric acid on the foaming process, physicomechanical performance, and thermal stability were investigated. Moreover, the thermal degradation behavior of the MCP-based RPUFs was also investigated. The various MCPs exhibited high hydroxyl values (450–515 mg KOH/g) and low viscosities (1550–2150 mPa∙s). In addition, citric acid had a positive influence on the compressive strength and thermal stability of the MCP-based RPUFs. When the ratio of malic acid:citric acid was 95:5, the corresponding RPUF had a density of 42.6 kg/m 3 , a high compressive strength of ∼191 kPa, a low thermal conductivity of 0.0365 W/(m K), and a high initial thermal degradation temperature (> 280°C). Compared to commercial polyether polyols, the MCP-based, water-blown RPUFs demonstrated lower apparent densities, lower thermal conductivities, and higher normalized compressive strengths. These results demonstrated that malic- co -citric acid-based polyols could be an adequate substitute for petrochemical-based polyols for providing water-blown RPUFs with excellent comprehensive properties.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RESEARCH
·
2020
·Vol. 28
·期 11
·1032-1039
·
IF 2.047
Xu Chang-An,Lu Mangeng,Wu Kun,Shi Jun
Polyurethane (PU) elastomer has been widely used in many fields. In this work, polyurethane/polysiloxane elastomers are synthesized by one-step polymerization using polyether and polyester polyols. The properties of polytetramethylene ether glycol (PTMG) and polycarbonate (PCDL) on polyurethane/polysiloxane elastomers are characterized by various test methods. The results show that PTMG is superior to PCDL in heat resistance and hydrophobicity to polyurethane/polysiloxane elastomers. The heat resistance index of PTMGPU is as high as 154 °C, and its contact angle has reached 115.2°. In addition, the surface of PTMGPU contains more silicone. This may be because the chain structure of PTMG is conducive to the migration of siloxane to the surface, and then a Si-O-Si protective layer is formed, thereby improving the heat resistance and hydrophobicity of the surface of PTMGPU. PCDLPU shows good mechanical properties, which may be related to the stronger chain structure of PCDL. This provides a theoretical basis for the future application of polyurethane/polysiloxane materials.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2018
·
IF 1.712
Wei Zhou,Puyou Jia,Yonghong Zhou,Meng Zhang
Three kinds of tung oil-based structural flame retardants polyols (TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycerol by sodium methoxide. The products after transesterification were epoxidized by peracetic acid which was in-situ generated from acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst. And then, TOFPs were prepared from epoxidized alcoholysis tung oil (EGTO) with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), diethyl phosphate (DEP) and diethanolamine (DEA) by ring-opening reactions, respectively. GPC was used to evaluate the conversion rate, at optimum reaction conditions, selectivity for monoglyceride in transesterification. The influence of different parameters such as temperature, mole ratio or mass ratio on the conversion rate of transesterification and epoxidation were investigated. The molecular structures of TOFPs were characterized by FTIR and 1 HNMR. Finally, tung oil-based polyurethane foams (TOPUFs) were prepared by a one-shot process using TOFPs with polyisocyanate. The LOI values of TOPUFs whose content of DOPO-EGTO, DEP-EGTO and DEA-EGTO were 100 wt% can reach to 26.2%, 25.1%, and 24.4%, respectively.
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
CELLULOSE
·
2017
·Vol. 24
·期 6
·2403-2413
·
IF 3.417
Xu Siquan,Yan Xiaopei,Bu Quan,Xia Haian
A series of carbon nanotube (CNT)-supported monometallic Pd and bimetallic Pd–Fe catalysts were synthesized and employed for catalytic hydrogenolysis of cellulose into polyols, including hexitol, ethylene glycol (EG), 1,2-propanediol (1,2-PG), and glycerol (Gly). The physicochemical properties of the catalysts were characterized by nitrogen physical adsorption measurements, X-ray diffraction analysis, transmission electron microscopy, and X-ray photoelectron spectroscopy. The total yield of hexitol, EG, 1,2-PG, and Gly in hydrolytic hydrogenation of cellulose was 37, 55, and 53% for Pd/CNTs, Pd–Fe/CNTs (Pd:Fe = 1:1), and Pd–Fe/CNTs (Pd:Fe = 1:2), respectively. Addition of Fe to Pd significantly modified the physicochemical properties of the nanoparticles and their catalytic performance, especially regarding hexitol selectivity. The promoting effect of Fe, especially for hexitol selectivity, compared with the monometallic catalyst is due to the fact that incorporation of Fe may stabilize Pd 0 nanoparticles and lead to downshift of the d -band center of Pd metal nanoparticles by charge transfer from Fe to Pd. Recycling experimental results showed that leaching of Fe resulted in a significant decrease in the hexitol yield obtained using the Pd–Fe/CNTs after the first recycle, further demonstrating that Fe element plays a promoting role for hexitol formation.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2023
·
IF 3.7
Shuang Luo,Jingwei Li,Jiansu Ran,Ruixue Yangcheng,Yuntong Cui,Yuxin Zhang,Jianjian Wang
A novel catalyst prepared by a facile ‘one-pot’ solvothermal method was developed for the efficient production of lower polyols from glucose solution. Under the optimal reaction conditions, the yield of diols was up to 50.7%, outperforming the recent works reported in the literature (<48%). Deeper investigation results revealed that the modification of MgO y on Pt-WO x could tune the surface acid-base properties, thereby promoting the yield of lower polyols. Combining the experimental and characterization results, a possible reaction mechanism during the conversion of glucose to lower polyols over Pt-WO x -MgO y was proposed.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Renewable and Sustainable Energy
·
2017
·Vol. 9
·期 2
·
IF 1.135
Xiao Zhuqian,Mao Jianwei,Jiang Chengjun,Xing Chuang,Ji Jianbing,Cheng Yongjie
The direct hydrogenolysis of cellulose on bimetallic catalysts represented a promising route for polyols' production. The development of a catalyst system that could control the promotion of the selectivity of polyols for the conversion cellulose into polyols was highly desirable. In this work, we realized the production of ethylene glycol (EG) and 1,2-propylene glycol (1,2-PG) by adopting nano-Sn species with different valences in combination with Ni catalysts, and the catalysts were prepared by the incipient-wetness impregnation method. The catalyst 10%Ni–15%Sn/SBA-15 achieved the highest yield of C 2 -C 3 polyols, yielding up to 67.2% with a higher selectivity to 1,2-PG. The Ni and Sn species and some NiSn alloys were found to be the active sites for the EG and PG as evidenced by control experiments and characterization including X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. The catalytic particles were located on the outer surface of SBA-15 (pore size = 6–10 nm) on a nanoscale with sizes of 11.1 ± 1.9 nm. The effects of the supports and hydrogenating species were investigated for cellulose conversion. The experimental results disclosed that the Sn species with different valences possessed obvious functions for the retro-aldol condensation, and the Ni components boomed the hydrogenation process. The other detailed analyses on the formation of polyols were described. As a consequence, controlling the EG and PG product distribution could be realized using Sn based catalysts.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2015
·
IF 2.358
Jie Yi,Congshu Huang,Haiyan Zhuang,Hui Gong,Chuyi Zhang,Runtao Ren,Yupu Ma
The star-shaped polyester polyols based on initiators (trimethylolpropane or pentaerythritol) and ɛ-caprolactone were prepared by polycondensation reaction. The degradable polyurethane (PU) films were prepared by mixing star-shaped polyester polyols and crosslinker agent (hexamethylene diisocyanate trimer). The hydrolytic degradation and water absorption experiments demonstrated that the PU films could erode in artificial sea water, which were controlled by varying the ratios of ɛ-caprolactone/trimethylolpropane and the arm number of star-shaped polyester polyols. The mechanical properties of PU films and coatings increased with decreasing the ratios of ɛ-caprolactone/trimethylolpropane and increasing the arm number of star-shaped polyester polyols. The surfaces of PU films and coatings kept eroding, which were revealed by scanning electron microscopy. The copper ion release rates from PU coatings reached steady state at about 31 days. The marine field tests of PU coatings demonstrated that the degradable PU coatings based on star-shaped polyester polyols were effective coatings for marine antifouling.
研究领域:
材料科学
·
海洋生物学
·
化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Wei Wang,Dong Wang,Bihua Xia,Ting Li,Yang Wang,Xuhui Zhang,Huiyu Bai,Mingqing Chen,Weifu Dong
To alleviate the exhaustion of petrochemical resources and reduce their use in the polyurethane industry, biopolyols derived from dextrin and glycerol were prepared and used in rigid polyurethane foam (RPUF). Through simple and eco-friendly physical mixing, biopolyols with different dextrin contents were obtained, and the effects of different biopolyols on the foaming process, combustion behavior, mechanical properties and biodegradability were investigated. The apparent density of the RPUF ranged from 31.4 kg/m 3 to 49.1 kg/m 3 . Compared with conventional foam, RPUF based on dextrin and glycerol had a higher normalized compressive strength and biodegradability. In addition, when the ratio of dextrin to glycerol in the biopolyol was 1/1, the self-extinguishing time of the foam was only 9 s, and the LOI value was 14.5% higher than that of conventional foam. These results demonstrated that dextrin-glycerol polyols can completely replace petrochemical polyols to prepare water-foamed RPUF with excellent comprehensive properties.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY
·
2023
·Vol. 100
·期 7
·561-577
·
IF 2
Shuai Wang,Fukai Yang,Wei Sun,Xinyu Xu,Yuyuan Deng
Rigid polyurethane foam (RPUF) is prepared from petroleum-based polyols and isocyanate, which consumes a large amount of petroleum. To alleviate the consumption of petroleum, it is necessary to synthesize green and sustainable polyols. However, the greatest disadvantage of RPUF is its flammability. To reduce the risk of fire caused by RPUF, phosphorylated soybean oil polyol (Polyol-P) and phenyl phospho-soybean oil polyol (Polyol-PPOA) were synthesized by ring-opening reactions of epoxy soybean oil with phosphoric acid and phenylphosphonic acid, respectively. A flame-retardant RPUF was prepared via polymeric 4,4-diphenylmethane diisocyanate (p-MDI), which reacted after mixing Polyol-P and Polyol-PPOA with polyether polyol-330N in different proportions. Scanning electron microscopy (SEM) showed that the cell sizes of the RPUF-P and RPUF-PPOA increased first and then decreased and the cell number decreased first and then increased with the increase in the contents of Polyol-P and Polyol-PPOA. Mechanical property tests showed that the compressive strength of the RPUF-P4 reached 0.1 MPa, and the compressive strength of the RPUF-PPOA4 reached 0.07 MPa. The limiting oxygen index values of the RPUF-P4 and RPUF-PPOA4 were 20.9% and 24.3%, respectively. The UL 94 of the RPUFs indicated that the rating of the RPUF-PPOA3 was improved to V-1. The results showed that the flame-retardancy mechanism of the Polyol-P and Polyol-PPOA in the RPUF was based on the charred surface as a physical barrier, which slowed down the decomposition of RPUF and prevented heat and mass transfer between the gas and the condensed phase.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Yaoyao Zhang,Ping Li,Shangde Sun
Herein, a novel synthetic strategy for the preparation of soybean oil-based biopolyol has been established using ionic liquids (ILs) as the green and efficient catalysts via the ring-opening reaction of epoxidized soybean oil (ESO) with glycerol as the nucleophile. Among them, the sulfonic-functionalized IL 1-butylsulfonic-3-methylimidazolium trifluoromethanesulfonate ([BSO 3 HMIM]OTF) exhibited superior catalytic performance in the ring-opening reaction under mild reaction conditions, demonstrating excellent catalytic efficiency and a high hydroxyl number of the synthesized biopolyol products. The impacts of various reaction variables on the ring-opening reaction were systematically investigated employing one variable at a time (OVAT) and response surface methodology (RSM). Under the optimized reaction parameters, including a catalyst loading of 1.2 wt%, a reaction duration of 4 h, a molar ratio of glycerol to epoxy groups of 3:1, and a tert -butanol to substrate of 1:1 (w/w) at 45 °C, the highest epoxy group conversion rate and the hydroxyl number were found to be 98.0 ± 0.6 % and 285.0 ± 1.4 mg KOH/g, respectively. Characterization by NMR and FT-IR confirmed the successful synthesis of biopolyols, while thermal stability and rheological studies further highlighted their suitability for diverse industrial applications as valuable chemical intermediates. These findings underscore the potential of sulfonic-functionalized [BSO 3 HMIM]OTF IL as efficient and eco-friendly catalyst in sustainable biopolyol production.
研究领域:
化学工程
·
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Xinyan Wang,Yaqi Cao,Jia Zhang,Haibin Yu
Polyurethane pressure-sensitive adhesives (PSAs) were synthesized by reacting isophorone diisocyanate (IPDI) with mixtures of different biobased polyols, where polylactide diol (PLA 1000) acted as a hard polyol and cashew nut shell liquid (CNSL)-derived diol and castor oil (CO) acted as soft segments. Besides, CO played another role in the synthesis of the polyurethanes as a cross-linker to enhance the cohesion of the prepared PSAs. The effects of different ratios of polyols and NCO/OH on microphase separation, thermal, rheological, and adhesive properties of the polyurethane were comprehensively studied. A balanced PSA with excellent tack and sufficient peel strength was prepared by adjusting the ratio of different polyols at PLA1000/CNSL diol/CO = 4:4:2 and a suitable NCO/OH value of 0.70. Eventually, the biodegradability of PSA 442-0.70 was investigated, and the biodegradation rate reached 64.47% within 8 weeks, making it a promising environmentally friendly adhesive tape for packaging applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Rong Liang,Jiahui Yang,Chunhuan Liu,Cheng Yang
The low solubility of quercetin considerably decreases its loading efficiency in traditional water and oil-based emulsion systems, which has limited their applications. To find a solution to this issue, in this investigation, polyol consisting of dipropylene glycol and glycerol as a solvent was used to increase quercetin solubility. It was further incorporated in polyol-in-oil-in-water Pickering double emulsions stabilized by SiO 2 . The characterization of these Pickering double emulsions was performed by analyses of their microscopic structures, particle sizes, rheology, and storage stability. The rise in the concentration of quercetin from 0 to 0.60 wt% decreased the droplet size of these emulsions and increased their viscoelasticity and storage stability. The microstructure of the emulsions showed the presence of some quercetin on the water-oil interface, suggesting that this bioactive compound might have recrystallized from the internal polyol phase during the preparation and then acted as a particle stabilizer in synergy with SiO 2 . To test and validate this hypothesis, we examined the Pickering stabilization properties of the recrystallization quercetin and its interaction with SiO 2 . We found that the recrystallized quercetin interacted with SiO 2 through a hydrogen bond and co-stabilized the interface. Additionally, it also served as a thickener that was involved in the development of an intense entangled network structure that connected the droplets, which improved the emulsion stability. These results revealed an effective approach for the preparation of stable Pickering double emulsions with high quercetin loading.
研究领域:
食品科学
·
材料科学
·
生物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）