MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 18
·2000217
·
IF 2.335
Yujian Liu,Qun Jia,Yuansheng Ding,Yougen Chen
The current work describes the synthesis of novel polyacrylate-based polyurethanes through the polyaddition of hexamethylene diisocyanate (HDI) with α,ω -hydroxyl end-functionalized polyacrylates (HO-PA-OHs), including α,ω -hydroxyl end-functionalized poly( n -butyl acrylate) (HO-P n BA-OH), poly( n -octyl acrylate) (HO-P n OA-OH), and poly( n -lauryl acrylate) (HO-P n LA-OH), respectively. HO-PA-OHs are prepared by the N- (trimethylsilyl)bis(trifluoromethanesulfonyl)imide (Me 3 SiNTf 2 )-catalyzed group transfer polymerizations (GTPs) of n -butyl acrylate ( n BA), n -octyl acrylate ( n OA), and n -lauryl acrylate ( n LA) in toluene at room temperature using the functional 1-(2-triisopropylsiloxyethoxy)-1-triisopropylsiloxy-2-methyl-1-propene as an initiator and the low ceiling temperature acrylate, 2-(triisopropylsiloxy)ethyl α-phenylacrylate, as a terminator, followed by the desilylation of the resulting α,ω -triisopropylsiloxy end-functionalized polyacrylates ( i Pr 3 SiO-PA-OSi i Pr 3 s) using tetra- n -butylammonium fluoride (TBAF). The polyaddition reactions between HO-PA-OHs and HDI are carried out in toluene using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the catalyst to afford the target polyacrylate-based polyurethanes. The polymer structures are characterized by 1 H NMR spectroscopy and FT-IR measurements. The thermal properties of the resulting polyacrylate-based polyurethanes are investigated by differential scanning calorimeter.
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
RSC Advances
·
2018
·Vol. 8
·期 61
·35014-35022
·
IF 2.936
Menglu Song,Xiangui Yang,Gongying Wang
γ-Al2O3 loaded with potassium nitrate (KNO3/Al2O3) catalysts were prepared, characterized and employed as a type of heterogenous solid base catalyst in the synthesis of polycarbonate (1,4-butane carbonate)-diol (PBC–OH) via the transesterification of dimethyl carbonate (DMC) and 1,4-butanediol (BD). The relationship between physicochemical properties and catalytic performance for KNO3/Al2O3 in this transesterification reaction was investigated using various techniques. The results demonstrated that the performance of KNO3/Al2O3 catalysts was highly influenced by basic site amount and strength. The medium and strong basic sites were beneficial for this reaction. The catalyst with a KNO3 loading of 35% and a calcination temperature of 700 °C exhibited the best catalytic activity due to its highest basic site amount and appropriate base strength. The highest BD conversion and PBC–OH yield of 80.2% and 68.4% were obtained under optimal reaction conditions. Also, this solid base catalyst was successfully employed in the synthesis of copolycarbonate diols from DMC and two different diols. Different scanning calorimetry results indicated that the thermal properties of the copolycarbonate diols can be adjusted by regulating the average segment lengths, Mn and copolymer composition structure.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2022
·
IF 6.064
Li Menglu,Jing Jing,Su Tingting
Poly(hexylene succinate) (PHS), poly(ethylene succinate) (PES), and their random copolyesters, poly(hexylene succinate-co-ethylene succinate) ((P(HS-co-ES)), were synthesized by melting polycondensation. Simply varying the ratios of HS/ES afforded control over the copolymer crystallinity, thermal and mechanical properties, wettability, and enzymatic hydrolyzability as shown by X-ray diffraction (XRD), differential scanning calorimetry (DSC), tensile tests, and water contact angle (WCA) measurements. The enzymatic hydrolysis rates of all prepared copolyesters were higher than those of the corresponding homopolyesters. The hydrolysis rates were affected by crystallinity, melting temperature, and hydrophobicity of the copolyesters, and therefore, the degradation rates could be tuned along with the ES content. The library of copolymers prepared here with tunable degradation rates, ranging from HS-enriched to ES-enriched copolyesters, is promising for a variety of different applications. The P(HS-co-ES51) copolyester that did not fully degrade is particularly promising for use in long-term storage applications, whereas P(HS-co-ES13) and P(HS-co-ES76) that rapidly degrade are good for use in very short-term applications.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
3 Biotech
·
2023
·Vol. 13
·期 10
·1-11
·
IF 2.8
Zhao Zhenzhen,Liu Yanfeng,Liu Chao,Xu Qianqian,Song Meijie,Yan Hai
Extensive use of phthalic acid esters (PAEs) as plasticizer causes diffusion into the environment, which posed a great threat to mankind. It was reported that Comamonas sp. was a potentially robust aromatic biodegrader. Although the biodegradation of several PAEs by Comamonas sp. was studies, the comprehensive genomic analysis of Comamonas sp. was few reported. In the present study, one promising bacterial strain for biodegrading diethyl phthalate (DEP) was successfully isolated from activated sludge and characterized as Comamonas sp. USTBZA1 based on the 16S rRNA sequence analysis. The results showed that pH 7.5, 30 °C and inoculum volume ratio of 6% were optimal for biodegradation. Initial DEP of 50 mg/L could be completely biodegrade by strain USTBZA1 within 24 h which conformed to the Gompertz model. Based on the Q-TOF LC/MS analysis, monoethyl phthalate (MEP) and phthalic acid (PA) were identified as the metabolic products of DEP biodegradation by USTBZA1. Furthermore, the whole genome of Comamonas sp. USTBZA1 was analyzed to clarify the molecular mechanism for PAEs biodegradation by USTBZA1. There were 3 and 41 genes encoding esterase/arylesterase and hydrolase, respectively, and two genes regions ( pht 34512 and pht 4253) were responsible for the conversion of PA to protocatechuate (PCA), and two genes regions ( lig CBAIKJ) were involved in PCA metabolism in USTBZA1. These results substantiated that Comamonas sp. USTBZA1 has potential application in the DEP bioremediation.
研究领域:
环境生物学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Ning Wang,Nan Zhang,Mei-Ling Sun,Yan Sun,Qing-Yu Dong,Yu Wang,Zeng-Tian Gu,Hai-Tao Ding,Qi-Long Qin,Yong Jiang,Xiu-Lan Chen,Yu-Zhong Zhang,Chao Gao,Chun-Yang Li
Phthalate esters (PAEs) are emerging hazardous and toxic chemicals that are extensively used as plasticizers or additives. Diethyl phthalate (DEP) and dimethyl phthalate (DMP), two kinds of PAEs, have been listed as the priority pollutants by many countries. PAE hydrolases are the most effective enzymes in PAE degradation, among which family IV esterases are predominate. However, only a few PAE hydrolases have been characterized, and as far as we know, no crystal structure of any PAE hydrolases of the family IV esterases is available to date. HylD1 is a PAE hydrolase of the family IV esterases, which can degrade DMP and DEP. Here, the recombinant HylD1 was characterized. HylD1 maintained a dimer in solution, and functioned under a relatively wide pH range. The crystal structures of HylD1 and its complex with monoethyl phthalate were solved. Residues involved in substrate binding were identified. The catalytic mechanism of HylD1 mediated by the catalytic triad Ser140-Asp231-His261 was further proposed. The hylD1 gene is widely distributed in different environments, suggesting its important role in PAEs degradation. This study provides a better understanding of PAEs hydrolysis , and lays out favorable bases for the rational design of highly-efficient PAEs degradation enzymes for industrial applications in future.
研究领域:
环境科学
·
生物化学
·
酶学
·
结构生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2022
·Vol. 30
·期 8
·3209-3217
·
IF 4.705
Han Xiaolong,Jin Yujuan,Huang Jian,Tian Huafeng,Guo Maolin
Hyperbranched polymer with flexible long chains (Ɛ-CL) were synthesized based on hydroxyl terminated hyperbranched polyesters (HBPEs). The prepared HBP-CLs were used to toughen poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by melt-blending. Comparing with pure PHBV, the crystallinity (X c ) of the PHBV/3.0phr HBP-CLs blends decreased by 10.2% (from 67.8 to 60.9%), the impact strength increased by 533.3% (from 5.1 kJ·m − 2 to 32.3 kJ·m − 2 ), and the elongation at break increased by 160.5% (from 1.62 to 4.22%). With the increase of HBP-CLs, the fracture surface of the PHBV/HBP-CLs blends became rough and a significant decrease in crystallization area can be seen from POM images. Even filamentous structures and tiny holes was formed, which further demonstrated that HBP-CLs acted as an excellent toughening effect on PHBV.
研究领域:
材料科学
·
高分子科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2025
·
IF 7.3
Yafang Han,Ziyang Gong,Renjie Zhou,Weile Li,Jun Shi,Jiwen Hu
In modern industrial applications, achieving strong adhesion to low surface energy materials, such as polyethylene, polypropylene, and polytetrafluoroethylene, is a significant challenge. This is primarily due to their inherent chemical inertness and weak interfacial interactions. To address this challenge, this study developed a novel pressure-sensitive adhesive with an interpenetrating network (IPN) structure. This was achieved by synthesizing linear polyethylene glycol-based polyurethane acrylate (PUA) oligomers and combining them with polyacrylate pressure-sensitive adhesives (PSA) to form the IPN structure. By adjusting the content of PUA, the viscoelasticity, mechanical, thermal, and adhesive properties of the PSA-PUA system were successfully optimized. The results demonstrate that the PSA-PUA20 exhibits excellent adhesion performance on polyethylene(PE) substrates, with a peel strength of 364.75 N/m and a loop tack of 4.03 N. Compared to polyacrylate pressure-sensitive adhesives (PSA), these values represent increases of 240.25 % and 46.58 %, respectively. Additional lap shear tests further confirmed that the PSA-PUA20 enables cyclic adhesion on polytetrafluoroethylene (PTFE) substrates. A mechanistic analysis reveals that the incorporation of PUA alters the surface energy of the adhesive, improving its spreading properties on low surface energy materials. Additionally, it strengthens the hydrogen bonds and van der Waals forces between molecular chains, significantly improving the cyclic shear performance and adhesion performance on low surface energy substrates. Furthermore, the PSA-PUA adhesive exhibits excellent antioxidant and thermal stability, offering a promising solution for the design of high-performance PSAs.
研究领域:
材料科学
·
高分子化学
·
工业应用
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Chuang Yang,Yufei Zhang,Yuanzhi Xu,Yibin Zhou,Shiyi Li,Mingming Zheng
An applicable and highly efficient methodology for the preparation of medium- and long-chain triglycerides (MLCTs) via the enzymatic transesterification of coconut oil with long-chain fatty acid triglycerides, named camellia oil, olive oil, linseed oil, algal oil, and rapeseed oil, respectively, has been proposed. The novel system achieved equilibrium in 5 min, and the MLCT yield ranged from 78.7 to 83.8 %. This is the fastest record reported to date. The catalytic efficiency of the novel biocatalyst, CSL@HMS-C 8 , was 140 g/g•h, 1.43 times higher compared to the control (free lipase), and it retained 62.5 % of its relative activity after 15 cycles. A UPLC-MS provided an accurate structural analysis of the MLCTs, and molecular docking analysis was performed to understand the binding interactions between the protein and molecules. The method of preparing MLCT enriched with functional fatty acids in this paper is efficient, broadly applicable, economical, and promising for industrial applications.
研究领域:
生物化学
·
食品科学
·
工业生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Tongyi Wu,Xiangqin Ding,Kaifeng Yuan,Tianhua Liu,Guoqiao Lai,Qiu Chen
Single UV-curing silicone-modified polyurethane acrylate materials have limitations, such as low molecular polymerization and weak mechanical properties compared to thermal-curing materials. This experiment synthesized a polyurethane prepolymer coated with isocyanate groups using hydroxyl polyether silicone oil (PDMS) and diisocyanate. tert-Butylaminoethyl methacrylate (t-BAEMA) was then utilized to create a silicon-modified polyurethane acrylate (SiBPUA) prepolymer with heat-unstable urea and photosensitive groups. This prepolymer was incorporated into photosensitive resin materials and processed through 3D DLP 3D printing. Upon heating, the −NCO group regenerated, and the chain extender underwent a secondary curing reaction, increasing molecular weight and improving performance. The study investigated the impact of different reactants on SiBPUA properties, deblocking temperature, optimal curing temperature, and enhancement of UV-curing materials through thermal curing. The results revealed that the use of isophorone diisocyanate (IPDI), 4,4′-diaminodicyclohexylmethane (PACM), and methyl methacrylate (MMA) resulted in the best mechanical properties. Furthermore, UV-thermal dual curing significantly enhanced tensile strength (12.5 MPa) and elongation at break (219.5%), broadening the application potential of UV-curing 3D printing materials.
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
Polymers
·
2021
·Vol. 13
·期 22
·3977
·
IF 4.329
Chenglong Wang,Luyang Qiao,Qiang Zhai,Kai Yan,Lili Wang,Jinhuan Zheng
Herein, a polyurethane acrylate-based TiO2(PU-TiO2) was fabricated using a two-step method. First, a polyurethane prepolymer was prepared. Second, PU-TiO2was prepared using amino-modified TiO2(A-TiO2). The best synthesis process of the polyurethane prepolymer was when the reaction temperature was 80 °C, the reaction time was 3 h and theR-value of the polyurethane acrylate was 2. Next, the influence of the A-TiO2content on the structure and performance of PU-TiO2was examined. The analysis of the rheological properties of the PU-TiO2ink indicated that its viscosity gradually increased as the A-TiO2content increased. The tensile performance of film improved because of the presence of A-TiO2. The photo-polymerisation and photo-rheological performance indicated that the PU-TiO2structure changed from a hyperbranched structure with TiO2as the core to a segmented structure, as the A-TiO2content was 3%.Keywords:polyurethane acrylate-based TiO2;polyurethane prepolymer;A-TiO2;hyperbranched structures;blue light-curable ink
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
International Journal of Polymeric Materials and Polymeric Biomaterials
·
2016
·
IF 1.667
Zhaosheng Hou,Hao Zhang,Wenqiang Qu,Zhen Xu,Zheng Han
In the study, a new approach for synthesizing biomedical segmented polyurethanes (SPUs) based on polyethylene glycol (PEG, Mn = 800), poly(ε-caprolactone-co-D,L-lactide) (PCLA) and aliphatic diurethane diisocyanates with a long uniform hard segment was developed. By the chain extension of a mixture of PEG diol and PCLA diol with diurethane diisocyanates based on inexpensive 1,6-hexanediisocyanate, three SPUs (SPU-I, SPU-II, and SPU-III) with different contents of hydrophilic segments (PEG) and hard segments were obtained. The chemical structures of diurethane diisocyanates, PCLA and SPUs were confirmed by 1H NMR, 13C NMR, FT-IR, HR-TOF-MS, and GPC. The SPU films exhibited similar thermostability, indicating that the hard segment content marginally affects on the thermostability. From the results of differential scanning calorimetry, two glass transition temperatures were observed, suggesting the microphase separation of soft and hard segments. The SPU films exhibited satisfactory mechanical properties with ultimate stress of 17.4–22.3 MPa and strain at break of 890–1060%, and the initial modulus increased with the increasing content of hard segments. In vitro degradation studies indicated that the time of SPU films to become fragments was 22–33 days, and the degradation rate increased with the increasing content of hydrophilic segments in SPU. Hence, the degradation time of SPU films could be controlled by adjusting the PEG content in SPU, which made them good candidates for further biomedical applications. Studies of in vitro drug release were conducted using vitamin B1 as model drugs. Drug-loaded films exhibited a high initial release rate and matrix-controlled release for more than two weeks, thereby demonstrating a promising material for a long-acting controlled release system. Cytotoxicity test of film extracts and cell attachment on the film surface were conducted using L929 mouse fibroblasts, and the results indicated that the SPU films possess excellent cytocompatibility and cell adhesive ability.
研究领域:
生物医学材料
·
高分子化学
·
药物释放系统
✓ 已验证
产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2015
·Vol. 73
·期 3
·647-659
·
IF 1.438
Liu Jingcheng,Liu Qiuhua,Zheng Xiangfei,Liu Ren,Mu Qidao,Liu Xiaoya
Two kinds of UV-curable polyurethane acrylates (PCDL-H-PUA and PCDL-P-PUA) were synthesized starting with polycarbonate diols (PCDL), isophorone diisocyanate and dimethylolpropionic acid and terminated with hydroxyethyl methacrylate or pentaerythritol triacrylate to impart mono-methacrylate or tri-acrylate end-group functionality, respectively. The structures and properties of the products were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, gel permeation chromatography and thermogravimetric analysis. The average molecular weights were between 7500 and 9300 g/mol, and the thermal properties of the products were excellent. The influence of the functionality of the end-capping functional group on the UV-curing behavior was investigated using real-time spectroscopy. Results showed that curing rate and conversion of PCDL-P-PUA were higher than those of PCDL-H-PUA, and the final double bond conversion of the polymers reached 95 %. PCDL-H-PUA and PCDL-P-PUA were applied to negative photoresists as the main film resin. The resolution of the optimal photoresist reached 40 µm.
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
危险品化学品经营许可证（带存储）