E-POLYMERS
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2022
·Vol. 22
·期 1
·544-552
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IF 3.074
Sheng Ding,Jinxing Zhu,Saiqi Tian
Polyurethane-based retanning agents with antimicrobial properties were synthesized by the chemical incorporation of ciprofloxacin (CPFX) units into polyurethane chains. The chemical structures were characterized by Fourier transform infrared (FTIR) and gel permeation chromatography (GPC). Then, the retanning agents were applied in the leather retanning process. Owing to the conjugation of CPFX into polyurethane chains, the molecular weight increases, further leading to the decrease in hydroxyl value and increase in particle size. The shrinkage temperature was improved after retanning. Owing to the filling of retanning agents in the gap of collagen fibers, the average thickness of leather increased by 65.8%. The mechanical properties of leather were visibly improved because of the large number of –COOH coordinate with Cr 3+ and more hydrogen crosslinking with carboxyl group, amino group, and hydroxyl group of leather collagen. Furthermore, leather retanned by these polyurethane-based retanning agents presented good antimicrobial properties. The antibacterial activity could be conserved above 89% even after rinsing for ten times.
研究领域:
化学工程
·
材料科学
·
生物学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Fei Pan,Yuanhang Xiao,Long Zhang,Jiajing Zhou,Chunhua Wang,Wei Lin
Eco-friendly keratin-based retanning agents have aroused widespread interest in leather manufacturing, because they recycle the biomass wastes for sustainable industry. However, the poor filling effect and binding strength of hydrolyzed keratin from bovine hair wastes limit its application for leather retanning. Here we reported a series of polyacrylate-modified keratin (PMK) retanning agents synthesized from vinyl monomers and bovine hairs via a surfactant-free and UV-initiated polymerization. The obtained spherical PMK retanning agents exhibited ideal characteristics, such as appropriate molecular weight (13–22 kDa) and particle size (86–110 nm), and good colloidal stability in the tanning bath (pH 5.5). We further validated these agents for retanning bovine shoe upper leather. Compared with FB (i.e., a commercial retanning agent), leather retanned with PMK 75 showed increased thickness (∼50%) and reduced Δ b * (∼80%), suggesting excellent filling properties and yellowing resistance. Moreover, the retanning agent afforded the products improved physical properties (e.g., tensile strength ∼17.3 N/mm 2 , tear strength ∼72.7 N/mm and elongation at break ∼75.4%) and sensory properties (e.g., compression thickness ∼0.25 mm and resilience thickness ∼0.21 mm). This work not only offered a robust method for preparing low-cost retanning agents in sustainable industry, but also provided more opportunities for recycling biomass-based wastes aiming to closed-loop economy.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Reaction Chemistry & Engineering
·
2023
·Vol. 9
·期 1
·199-208
·
IF 3.9
Jianzhong Ma,Jiamin Zhao,Hui Zhang,Zhenhua Tian,Qiwu Liu,Na Yang,Wenbo Zhang
Acrylic polymers are widely used in pharmaceutical, leather, textile and other industries, and are prepared via the polyreaction of acrylic monomers, such as acrylic acid, acrylamide and acrylic esters. Acrylic acid and acrylamide have been proven to participate in the Mannich reaction to achieve cationization; however, the Mannich reaction of methyl acrylate has not been reported. At present, the main role of catalysts in the Mannich reaction is to provide products of specific spatial configuration, and there are few studies on improving the degree of cationic modification. The participation of acrylic acid, acrylamide and methyl acrylate in the Mannich reaction by means of the catalyst NaH was studied in this work. The optimal reaction conditions for the homopolymers were obtained via orthogonal experiments. At room temperature, the optimal reaction conditions for polyacrylic acid were as follows: the molar ratio of polyacrylic acid, glutaraldehyde and diethanolamine was 1.0 : 1.4 : 1.0, and the amount of catalyst was 7%. The optimal reaction conditions for polyacrylamide were as follows: the molar ratio of polyacrylamide, glutaraldehyde and diethanolamine was 1.1 : 1.1 : 1.2, and the amount of catalyst was 9%. The optimum reaction conditions for methyl polyacrylate were as follows: the molar ratio of methyl polyacrylate, glutaraldehyde and diethanolamine was 1.1 : 1.2 : 1.0, and the amount of catalyst was 9%. As a result, the maximum degrees of modification of polyacrylic acid, polyacrylamide and methyl polyacrylate were 63.0%, 33.5% and 39.0%, respectively. The range analysis of the orthogonal experiments showed that the effects on the modification degree of vinyl homopolymers, in sequence from strong to weak, were as follows: amount of catalyst > amount of amine > amount of aldehyde. Subsequently, polyacrylate–acrylamide–methyl acrylate (P(AA–AM–MA)) was synthesized using acrylic acid, acrylamide and methyl acrylate as monomers, and then modified via the catalyzed Mannich reaction. A novel amphoteric acrylic acid copolymer retanning agent (HCP(AA–AM–MA)) with a 50.2% degree of modification was obtained, and its properties as a retanning agent in leather-making were investigated. The dye-uptake and K/S value of the dyed leather retanned with HCP(AA–AM–MA) were 91.5% and 18.5, respectively, an increase of 18.4% and 3.4 in comparison with those of dyed leather retanned with P(AA–AM–MA). The results indicated that the dyeing-assistant performance of HCP(AA–AM–MA) was improved. Moreover, the elongation at break and tensile strength of the retanned leather were 82.0% and 31.9 MPa, respectively, which were higher than those of P(AA–AM–MA)-retanned leather (78.9% and 27.4 MPa).
研究领域:
化学工程
·
皮革科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Xuechuan Wang,Zhuan Yan,Xinhua Liu,Taotao Qiang,Liang Chen,Peiying Guo,Ouyang Yue
Chromotropic Acid Grafted Amphoteric Polyurethane (CAGAPU) was synthesized with Chromotropic Acid (CA) as a modifier for Polyurethane (PU). The structure of CAGAPU was confirmed by FT-IR, 1 H-NMR. The retanning process and the experiments of CAGAPU with formaldehyde indicate the following: (1) The leather retanned by CAGAPU can be comparable or surpassed to the market PU-based retanning system in terms of shrinkage temperature and sensory performance. (2) The leather collagen fibers are smoother and orderly which provides a potential value for the appearance of the leather and fur industry. (3) The CAGAPU retanned system can bring down the free formaldehyde content in aldehyde tanned leather significantly. (4) The optimum dosage of CAGAPU is 20 g and the best retanning time is 6 h (5) The CAGAPU retanned system can reduce the free formaldehyde, Biochemical Oxygen Demand (BOD), Total Dissolved Solids (TDS) and Total Suspended Solid (TSS) from the source which retard pound on the economy and environment greatly compare to the traditional governance. Therefore, this paper provides the possibility for the sustainable development of leather. The work has changed the traditional way of “terminal treatment” and realized the “initial treatment” and may also offer a new idea of solving the problem of formaldehyde in the newly decorated houses or in the air.
研究领域:
材料科学
·
环境科学
·
化学工程
·
皮革技术
✓ 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）