Coatings
·
2022
·Vol. 12
·期 9
·1271
·
IF 3.236
Fuquan Deng,Shuangyi Qin,Na Liu,Wei Xu
The hydrophobic modification effect and an appropriate cost of waterborne polyurethane are regularly pursued targets of researchers. To further enhance the hydrophobic modification effect of the terminal fluoroalkyl group and control the cost, a fluorine-containing pendant group diol (DEFA) was first synthesized by the Michael addition reaction of diethanolamine (DEOA) and dodecafluoroheptyl methacrylate (G04). Next, a series of modified polyurethane latexes (TPFPU) by the terminal fluoroalkyl segments (perfluorohexyl ethanol, S104) and the pendant fluoroalkyl segments (DEFA) were synthesized by varying the DEFA dosage. Structure and performance properties of the resultants were characterized by IR,1H NMR, TEM, TGA, DSC, XRD, XPS, SEM, AFM and contact angle measurements. Results confirmed that the product could be successfully prepared using the present method. With the increase in DEFA dosage, the average particle size increased gradually. Thermal stability was enhanced and small regional crystals were probably produced. XPS and AFM results demonstrated that the degree of microphase separation and film roughness were increased with the increase in DEFA amount. Hydrophobicity of the TPFPU’s film was also increased with the increase in DEFA dosage, and it could be guaranteed when the mass content of S104 and DEFA was larger than 17.0 wt% in total mass of raw materials, which demonstrates that the terminal and pendant fluoroalkyl groups have the favorable synergistic effect on the properties of polyurethane.Keywords:fluorinated polyurethane;branched polyurethane;hydrophobicity;synergistic effect
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
Polymers
·
2018
·Vol. 10
·期 2
·219
·
IF 2.935
Xin Chen,Chi Zhang,Weidong Li,Lei Chen,Wusheng Wang
A key for the preparation of polyacrylate-based polyurethane is the synthesis of hydroxyl-terminated polyacrylate. To our knowledge, exactly one hydroxyl group of every polyacrylate chain has not been reported. The hydroxyl-terminated poly(butyl acrylate) (PBA) has been successfully synthesized by degenerative iodine transfer polymerization (DITP) of then-butyl acrylate (n-BA) using 4,4′-azobis(4-cyano-1-pentanol) (ACPO) and diiodoxylene (DIX) as initiator and chain transfer agent, respectively, and subsequently substituted reaction of the iodine-terminated PBA with β-mercaptoethanol in alkaline condition. The latter reaction was highly efficient, and the terminal iodine at the end of polymer chains were almost quantitatively transformed to a hydroxyl group. 2,2′-Azobis(isobutyronitrile) (AIBN) and ACPO were used as initiators in the DITPs ofn-BA. The results demonstrated that they had a significant influence on the terminal groups of the formed polymer chains. The structure, molecular weight, and molecular weight distribution of the hydroxyl-terminated PBA have been studied by1H,13C NMR, and GPC results. The components of hydroxyl-terminated PBA were determined by MALDI-TOF MS spectra, and their formation is discussed. The broad molecular weight distribution of the PBA and the difference in the polymerization behaviors from typical living radical polymerization are explained based on the results of1H NMR and MALDI-TOF MS spectra. The hydroxyl-terminated PBA has been successfully used in the preparation of PBA-based polyurethane dispersions (PUDs). The aqueous PUDs were stable, and based on the DSC results it can be said that the miscibility of hard segments with PBA chains was improved.Keywords:poly(n-butyl acrylate);degenerative iodine transfer;free-radical polymerization;waterborne polyurethane
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainability
·
2022
·Vol. 14
·期 23
·15685
·
IF 3.889
Da-Sheng Zhang,Xiao-Hua Gu,Si-Wen Liu,Yan Liu,Qing-Yun Zhou,Shang-Wen Zhu,Yan-Wei Zhu
Polyurethane (PU) has become one of the most widely used materials in the industrial field due to its excellent performance and wide range of applications. The increasing consumption of polyurethane materials has resulted in significant polyurethane waste. We can recycle waste polyurethane to obtain recycled polyurethane, but to make the recycled polyurethane meet different performance requirements in terms of utility and cost and enable the recycled polyether polyol to be further applied to high-end applications, it is necessary to improve the use value of recycled polyether polyol. In this paper, self-made Fluorodiol was added to the degradation process of waste polyurethane to obtain fluorinated regenerated polyether polyol. Recycled fluorinated polyurethane with excellent performance was prepared using fluorine-containing recycled polyether polyol. The regenerated fluorinated polyether polyols were characterized by infrared spectroscopy, viscosity, hydroxyl value, and GPC molecular weight distribution. The density, apparent morphology, water absorption, mechanical strength, thermal conductivity, and thermal stability of RFPU rigid foams with different fluorine contents were studied by scanning electron microscopy. The results show that when the addition of Fluorodiol was 8% of the mass of waste polyurethane, the density was 41.2 kg/m3, the immersion loss rate was 2.125%, the compressive strength was 0.315 Mpa, and the thermal conductivity was 0.0227 W/m·K. The RFPU prepared by Fluorodiol has low surface energy, good compressive strength, hydrolysis resistance, and is expected to be widely used in special insulation materials. Thus, the sustainable recycling of polyurethane is achieved.Keywords:fluoroalcohol;waste polyurethane;recycled polyurethane;recycling;sustainable material
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Haiyan Liang,Yanchun Li,Siying Huang,Kaixi Huang,Xueyi Zeng,Qianwen Dong,Chengguo Liu,Pengju Feng,Chaoqun Zhang
Vegetable oil-based polymeric materials always suffer from relatively poor performance, such as lower tensile strength and glass transition temperatures, than petroleum-based polymeric materials, which greatly limit their practical applications. In this study, octahydro-2,5-pentalenediol (OPD) was synthesized from naturally occurring citric acid and used together with castor oil as the polyol blends for the production of bio-based waterborne polyurethane (PU) dispersions (PUDs). The effects of the OPD contents on the particle size and ζ potential of the resulting polyurethane dispersion, and the thermal stability, mechanical properties, and hydrophilicity of the resulting polyurethane films were systematically investigated. Taking advantage of the rigid cyclic structures of the OPD and the flexible fatty acid chain of castor oil, waterborne polyurethane (WPU) films with tailorable mechanical performance ranging from elastomeric polymers to rigid plastics were successfully prepared and characterized. The tensile strength of the samples increases from 9.5 to 22.3 MPa with the ratio between OPD and castor oil increasing from 0:10 to 5:5, whereas their elongation at break decreases from 192 to 12%. A significant increase in the glass transition temperature, transparency, and anticorrosive properties was observed for the resulting polyurethane films with increasing the OPD content. However, the thermal stability of the PU films exhibited a slight decrease as the OPD content increased. Moreover, the water contact angle exhibited a slight increase for the polyurethane films prepared from polyol blends compared to the WPU film prepared from pure castor oil. This work provides a novel route to tailor the performance of vegetable oil-based waterborne polyurethanes through the incorporation of rigid cyclic rings into soft polymer networks.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2023
·Vol. 61
·期 9
·748-760
·
IF 3.4
Li Wang,Haihang Luo,Qiang Gao,Le Jiang,Zhenya Wang,Haojun Fan,Yi Chen,Jun Yan,Jun Xiang
Bio-based polyols derived from vegetable oils generally contain the dangling chains, which have recently attracted significant attention due to their influence on the preparation and performance of the waterborne polyurethane. Herein, a novel undecylenic-based primary glycol (UPG) without dangling chains synthesized and the oleic-based primary glycol (OPG) with dangling chains reported by our previous work were used to prepare straight-chain and dangling-chain bio-based waterborne polyurethane (BWPU), respectively, to study the difference between the two diols and the effects of dangling chains on the synthesis and performance of BWPU. First, the UPG without dangling chains displayed higher activation energy ( E a / E o = 77.72/80.56 kJ mol −1 ) and longer reaction end point of prepolymer (240 min), indicating relatively lower reactivity to isocyanate. In addition, the dangling chains were found to influence the dispersion stability of BWPU, and the minimum dosage of DMPA for maintaining dispersion stability was 6.5 wt% for OPG but 5.5 wt% for UPG. The average particle size of BWPU is greater for OPG than for UPG with the same DMPA content. Finally, performance studies revealed that dangling-chain BWPU showed higher hydrophobicity, extensibility, and low temperature resistance, but lower thermal stability ( T d 5% ) and tensile strength. This work comprehensively clarified the effects of linear and branched bio-based polyols on the synthesis and properties of BWPU, and provided guidance for the development and application of bio-based polyols and BWPU coatings. Graphical
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
ACS Applied Polymer Materials
·
2023
·
IF 5
Fansen Meng,Donglin Tang
Vitrimers are generally constructed via crosslinking polymerization in which a crosslinker is reacted along with monomer(s). Herein, we report another strategy named group revival-induced crosslinking (GRIC) to prepare polyurethane vitrimer (PUV) directly from liner polyurethane (LPU) without using any crosslinker. Under the catalysis of K2CO3, the NH function in the urethane group is activated and it is able to attack another urethane group to form an allophanate crosslinker and, in the meantime, to release a free OH group. The allophanate is a dynamic covalent crosslinker in which reversible transesterification between free OH and allophanate groups allows the reprocessibilty for the obtained networks. The stress relaxation of the obtained networks prove the formation of the vitrimer. Both catalyst loading and vitrimerization temperature affect the gel fraction and further the mechanical properties of the obtained PUVs. Compared with LPU, the elongation at break of PUVs could be increased from 180 to 370%, while the tensile strength remains at the same level. Furthermore, the chemical structures and thermal and mechanical properties of the reprocessed PUVs remain the same as the pristine ones. This GRIC strategy is an efficient tool for enhancing the performance of thermoplastic polyurethanes (PUs) and, especially, for the value-added modification of recycled thermoplastic PUs as well as recycled polyamides.
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
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Mengqing Ren,Weilin Wu,Qingsong Shi,Lili Wu,Chaocan Zhang
The micropowder obtained by cryogenic pulverizing flexible polyurethane foam (FPUF) as a filler is a waste recycling approach which is highly efficient and eco-friendly. Currently, the micropowder has merely been applied roughly and simply in various fields, so it makes sense to study its surface activity in depth to achieve quantitative and efficient reuse. This paper is focused on studying the surface physicochemical properties of the micropowder and its reactivity and compatibility as a filler in polyurethane elastomers. The FPUF was pulverized into a particle of 0–900 μm. The hydroxyl and amine values of the micropowder surface increased from 48.82, 5.99 mg KOH/g to 73.78, 9.12 mg KOH/g, respectively, with the decrease of particle size range from 500-900 μm to 0–100 μm. However, the amount of substance of effective active hydrogens that could react with NCO groups in the polyurethane prepolymer was uncertain due to the viscosity and temperature. Thus, a preliminary attempt was to quantify the effective active hydrogens by FTIR coupled with titration of the NCO content. The mixture with 5% FPUF-1 micropowder had the maximum effective active hydrogens of 3.30 mmol, which could react with NCO groups to form new chemical crosslinking sites. Compared with the pure PU film, microcrosslinking and strong hydrogen bonding are contributors to the good mechanical properties of the composite. Thus, the FPUF micropowder as an organic filler exhibits considerable potential for converting thermoset FPUF into value-added performance materials.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Renewable Materials
·
2021
·Vol. 9
·期 11
·1913-1926
·
IF 1.67
Gu Xiaohua,Lyu Shiwei,Liu Siwen
A bi-component alcoholysis agent containing propylene glycol (PG) and ethanolamine (ETA) was used to catalyst the degradation of the waste polyurethane rigid foam. The oligomer polyols obtained through degradation were used as raw materials to produce recycled polyurethane rigid foam
composites with lignin as reinforcing filler. The effect of alcoholysis mass ratio on degradation was investigated by analyzing the viscosity, hydroxyl content and chemical structure of the degradation products. The effect of lignin addition on the properties of regenerated polyurethane rigid
foam were investigated by analyzing water absorption rate, compressive strength, porosity, thermal stability, thermal conductivity coefficient, morphology and thermal stability of the recycled polyurethane rigid foam. Results show that different mass ration of PG to ETA significantly affects
the degradation of waste polyurethane rigid foam. Besides, only with the addition of appropriate amount of lignin, the regenerated polyurethane rigid foam composites can meet the Chinese national standard "rigid polyurethane foam for building thermal insulation" (GB/T21558-2008). At this point,
the composite is with good mechanical and thermal prperties, including high compressive strength, excellent thermal insulation performance, complete cell morphology and good thermal stability.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Polymers
·
2020
·Vol. 12
·期 4
·836
·
IF 3.426
Chunhui Liu,Xi Liao,Weili Shao,Fan Liu,Bin Ding,Gaihuan Ren,Yanyan Chu,Jianxin He
Waterproof-breathable (WB) materials with outstanding waterproofness, breathability, and mechanical performance are critical in diverse consumer applications. Electrospun nanofibrous membranes with thin fiber diameters, small pore sizes, and high porosity have attracted significant attention in the WB fabric field. Hot-press treatment technology can induce the formation of inter-fiber fusion structures and hence improve the waterproofness and mechanical performance. By combining electrospinning and hot-press treatment technology, polyurethane/fluorinated polyurethane/thermoplastic polyurethane/alkylsilane-functionalized graphene (PU/FPU/TPU/FG) nanofiber WB fabric was fabricated. Subsequently, the morphologies, porous structure, hydrostatic pressure, water vapor transmission rate (WVTR), and stress–strain behavior of the nanofiber WB fabric were systematically investigated. The introduction of the hydrophobic FG sheet structure and the formation of the inter-fiber fusion structure greatly improved not only the waterproofness but also the mechanical performance of the nanofiber WB fabric. The optimized PU/FPU/TPU-50/FG-1.5 WB fabric exhibited an excellent comprehensive performance: a high hydrostatic pressure of 80.4 kPa, a modest WVTR of 7.6 kg m−2d−1, and a robust tensile stress of 127.59 MPa, which could be used to achieve various applications. This work not only highlights the preparation of materials, but also provides a high-performance nanofiber WB fabric with huge potential application prospects in various fields.
研究领域:
材料科学
·
纺织工程
✓ 已验证
DOI
高影响因子
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
·
2018
·Vol. 106
·期 8
·2131-2140
·
IF 3.231
Jun Zhang,Yutong Wang,Cheng Liu,Fuling Feng,Dawei Wang,Hong Mo,Ling Si,Guo Wei,Jian Shen
Expanded poly(tetrafluoroethylene) (ePTFE) has been widely used as a vascular graft material due to the fact that it is durable, porous, flexible, and inert. However, ePTFE grafts easily induce thrombosis, calcification and neointimal hyperplasia in small-diameter (<6 mm) graft bypass surgeries and thus cause surgical failure. Therefore, it is necessary to improve the in vitro and in vivo performances of ePTFE grafts. In this work, we first prepared a polyurethane/polyurethane nanoparticles (PU/PU-NPs) composite film by a simple cosedimentation method. Compared with the pure PU film, the blood compatibility and the cell compatibility of the PU/PU-NPs composite film were significantly improved. Then, we constructed a PU/PU-NPs/ePTFE vascular patch (PPVP) by coating PU and PU-NPs onto the surface of an ePTFE graft. PU-NP modification endowed the ePTFE graft with the nanopatterned surface similar to the luminal surface of a blood vessel. PU NPs and the structural likeness of the surface synergistically optimized the overall performance, and thus improved the blood and cell compatibilities, effectively inhibited platelet adhesion, enhanced cell attachment and proliferation, and facilitated the formation of endothelial tissue—endothelialization. The abdominal artery patched with PPVP was not blocked and the endothelialization was achieved 30 days after the implantation. All the results taken together indicate that PPVP may be a promising alternative for a vascular patch. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2131-2140, 2018.
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 136
·期 2
·46923
·
IF 1.901
B. Zhao,R. Jia,Y. Zhang,D. Liu,X. Zheng
Antibacterial waterborne polyurethanes (WPUs) have attracted increasing attention in a wide range of industrial applications because of their versatile properties as well as ecofriendly nature. Although extensive research has been carried out on antibacterial WBPU synthesis, the roles of some of the key synthesis components remain unclear. In this study, the novel chain extender DMG (dimethylol propionamide containing guanidine group) was designed and synthesized, which has not been reported before. DMG and the waterborne fluorinated polyurethanes containing DMG show high bactericidal (> 99.99%) efficacy against a broad spectrum of gram-positive and gram-negative bacteria. Furthermore, when the amount of DMG reached 5%, the average particle size of waterborne fluorinated polyurethane dispersions was 56.24 nm. And waterborne fluorinated polyurethanes showed good thermal (> 460 °C) properties and high crystallization with the increase of chain extender DMG. The successful synthesis of these fascinating antibacterial waterborne materials may provide new insights into the development of protection materials in a sustainable form, which could be applied as coatings in various fields to prevent microbial contamination. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 46923.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE AND ENGINEERING OF COMPOSITE MATERIALS
·
2021
·Vol. 28
·期 1
·528-539
·
IF 1.295
Su Xiaofeng,Yu Yitao,Li Bing,Wang Jing,Lu Chuan,Zong Jianping,Li Jinhui,Wang Feng
In order to prepare polyurethane–polysiloxane block copolymers, α,ω-hydroxyalkyl polysiloxanes with methacrylate side chain and α,ω-bis(2-methyl-3-hydroxypropyl)polymethyl(2-methyl-methylpropanoate) siloxanes, were synthesized and characterized in this study. The syntheses process included hydroxyl protection, hydrosilylation, deprotection, and ring-opening equilibrium reactions. The intermediates and target products were characterized by Fourier transform infrared spectroscopy and 1 H nuclear magnetic resonance methods. The characterization results showed that each step was successfully carried out in all the cases. Then the waterborne polyurethane–polysiloxane block copolymers were prepared via step-growth polymerization. The properties of the block copolymer films were characterized by thermal gravimetric analysis, differential scanning calorimetry, and dynamic thermomechanical analysis methods in detail. The experimental results showed that the block introduction of hydroxyalkyl polysiloxane could reduce the water absorption of waterborne polyurethane from 62 to 11%, and significantly improve the water resistance of polyurethane. With the introduction of polysiloxane, the tensile strength decreased and the elongation at break increased. At the same time, with the increase of the polysiloxane content, the glass transition temperature of the soft segment decreased to −56.4°C and the thermal decomposition temperature increased to 300°C. The results revealed that the introduction of polysiloxane could effectively improve the comprehensive performance of polyurethane–polysiloxane block copolymer films.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）