单组分阴离子水性聚氨酯

综述了单组分阴离子水性聚氨酯的性能特点、制备方法和原理以及国内外近期研究进展。指出单组分水性聚氨酯的发展趋势为：单一型向复合型、多功能型发展;单组分改水性聚氨酯是近期研究的重点和热点。     

Development of a method for the rapid determination of pentachlorophenol in leather using supercritical fluid extraction with in situ derivatization

Pentachlorophenol (PCP) was extracted from leather with supercritical carbon dioxide and in situ acetylated under static SFE conditions in the presence of triethylamine. During the dynamic extraction step, the derivatives were removed from the matrix and collected with either a pure liquid (light petroleum) or a liquid-solid (light petroleum-solid sorbent (C18, alumina, Florisil or Celite)) trap. To prevent restrictor plugging, a suitable restrictor was designed. The clean-up of the extracts was optimized in this study. Different internal standards were tested and it was shown that not all of them were usable. The SFE results were compared with those obtained by Soxhlet extraction with methanol. With SFE instead of conventional Soxhlet extraction, the overall time required for determination of PCP in leather can be reduced from about 2 days to approx. 3 hours.     

Ultrasound-assisted extraction of chromium from residual tanned leather: An innovative strategy for the reuse of waste in tanning industry

The tannery industry generates huge amount of waste with high Cr concentration, being classified as a dangerous waste. The development of alternative treatments for these residues aiming environmental friendly protocols are important topics of research. In this work, the use of ultrasound (US) energy for Cr removal from residual tanned leather was investigated. Ultrasound-assisted extraction (UAE) experiments were carried out in several systems as ultrasonic baths, cup horns, and probes, allowing to evaluate several frequencies (20–130 kHz) and power delivered to the extraction system. The following experimental conditions were evaluated: extraction solution (HCl, HNO₃, H₂SO₄, CH₂O₂ and C₂H₂O₄), temperature (10–90 °C), time (1–40 min), US amplitude (10–90%), feedstock amount (50–450 mg), and concentration of extraction solution (0.1–4 mol L⁻¹). A multivariate factorial design with 10 axial points and 3 central points was applied. After UAE optimization an efficiency of 92% was achieved for Cr removal using 150 mg of feedstock, 3 mol L⁻¹ HNO₃, at 30 °C, 90% of amplitude, and 30 min. The same efficiency was not observed using mechanical stirring (100–500 rpm), which was lower than 65%. To prove the applicability of the proposed process some experiments for scaling up were performed using several reactor loads (1–9 L). Moreover, using the proposed UAE process Cr was efficiently removed at lower reaction time and at room temperature only by using US and diluted acid solution, representing energy and reagents saving.     

超高效液相色谱-串联质谱法测定皮革中全氟辛烷磺酸和全氟辛酸

样品经甲醇索式提取180 min及复合式弱阴离子交换固相萃取柱富集,用氨水-甲醇(1+99)溶液从柱上洗脱PFOS和PFOA使净化。洗脱液在45℃氮气吹干,残渣用流动相乙腈-5 mmol.L-1乙酸胺(42+58)混合溶液溶解定容至5 mL,取10μL注入超高效液相色谱仪。以不同体积比的乙腈与5 mmol.L-1乙酸铵的混合溶液为流动相作梯度淋洗,经C18色谱柱(100 mm×2.1 mm,5μm)分离。采用电喷雾负离子源及多反应监测模式测定。PFOS和PFOA的质量浓度均在40.0μg.L-1以内呈线性关系,检出限(3S/N)均为1μg.L-1。在3个标准加入水平下进行了回收率和精密度试验,PFOS和PFOA的加标回收率分别在90.0%～99.4%和91.6%～104.0%之间,相对标准偏差(n=6)均不大于13%。     

Ultrasound assisted chrome tanning: Towards a clean leather production technology

Nowadays, there is a growing demand for a cleaner, but still effective alternative for production processes like in the leather industry. Ultrasound (US) assisted processing of leather might be promising in this sense. In the present paper, the use of US in the conventional chrome tanning process has been studied at different pH, temperature, tanning time, chrome dose and US exposure time by exposing the skin before tanning and during tanning operation. Both prior exposure of the skin to US and US during tanning improves the chrome uptake and reduces the shrinkage significantly. Prior exposure of the skin to US increase the chrome uptake by 13.8% or reduces the chrome dose from 8% to 5% (% based on skin weight) and shorten the process time by half while US during tanning increases the chrome uptake by 28.5% or reduces the chrome dose from 8% to 4% (half) and the tanning time to one third compared to the control without US. Concomitantly, the resulting leather quality (measured as skin shrinkage) improved from 5.2% to 3.2% shrinkage in the skin exposed to US prior tanning and to 1.3% in the skin exposed to US during the tanning experiment. This study confirms that US chrome tanning is an effective and eco-friendly tanning process which can produce a better quality leather product in a shorter process time with a lower chromium dose.     

气相色谱内标法测定皮革中五氯酚残留量不确定度评估

采用气相色谱内标法测定皮革中五氯酚残留量,对整个测量过程的不确定度来源进行了分析,并对不确定度各个分量进行了评估和合成,结果显示,样品重复性测量不确定度分量对总不确定度的贡献最大。当五氯酚测定结果为1.021 mg/kg时,扩展不确定度为0.056 mg/kg。按照相关计量规范要求,给出了五氯酚测量结果不确定的表达式。     

Synthesis and study of MPNS/SMA nano-composite tanning agent

The radical polymerization of maleic anhydride（MA）,styrene（ST）with the vinyl groups introduced onto the surface of the nano-sized silica via solution polymerization method was developed.The methacryloxypropyl nano-sized silica（MPNS）was used as macromonomer and polymerized with maleic anhydride and styrene by initiating with BPO in toluene.The structure and properties of MPNS/SMA nano-composite were characterized by FT-IR spectra and TEM.Meanwhile,it was applied as tanning agent compared with the traditional styrene-maleic anhydride copolymer in leather.It was found that the applied leather had better quality characteristics with the addition of the nano-sized silica.     

皮革中鞣性金属元素含量及分布的微波消解-ICP-AES研究

以新型无铬金属鞣剂鞣制的绵羊皮和猪皮为研究对象,以铬鞣绵羊皮和猪皮为对比。采用微波消解法处理试样,电感耦合等离子体-原子发射光谱法测定主要鞣性金属元素在皮革粒面层、中间层和肉面层的含量。锆在绵羊皮革各层的分布均匀性比猪皮好,正常鞣制皮革中粒面层的含量少于肉面层。钛在绵羊皮革粒面层的含量比例高于锆,在猪皮革粒面层的比例低于锆。绵羊皮革和猪皮革中铬的物质的量总量和各层含量都明显多于锆或钛,铬更容易进入猪皮的粒面层,不易进入中间层。     

皮革固体废弃物的高值转化

传统的制革工业在生产过程中要产生原皮重60%以上的固体废弃物，由于没有充分利用，成为造成制革工业污染严重的重要原因之一，随着资源，环境等全球性生态问题的日益严峻，制革废弃物的资源化，特别是高值转化，已成为国内外关注的重要课题，本文对作为天然的生物质资源的胶原适用于食品，医药和人妆品的属性及其应用以及从制革皮边角废弃物中提取胶原的方法作了简要论述。     

Standard additio--a way of improving quantification of banned azo dyes in leather

An analytical procedure based on supercritical-fluid extraction and microwave-assisted extraction was applied on six different real leather samples for the determination of banned azo dyes. Determination of the dyes was performed indirectly by measuring their corresponding harmful aromatic amines, formed after reduction. A comparative study between external standard calibration and standard addition using both the dyes as well as the corresponding amines showed that the latter quantification method provided the highest accuracy.