角质酶在涤纶织物表面改性中的应用

针对涤纶织物亲水性较差的问题,采用特异腐质霉(H.insolens)来源的角质酶对其表面进行改性。通过单因素变量试验对反应残液进行紫外光吸光度测试,确定角质酶处理涤纶织物的优化工艺条件:角质酶用量为100 U/mL,时间为72 h,pH值为8.5,温度为60 ℃。在此条件下,加入表面活性剂Trition X-100(为0.1%)能显著提高角质酶催化水解涤纶织物的产物释放量。测定了反应残液中产物的种类、处理前后织物的亲水性和染色性能,并对涤纶织物表面形貌以及表面化学成分进行表征,分析涤纶的酶法改性机制。结果表明:角质酶水解涤纶产物主要是单(对苯二甲酸-2-羟基乙酯)(MHET)和对苯二甲酸(TPA);角质酶处理后涤纶织物的接触角由93.4°降至83.1°;处理后织物的亚甲基蓝染色深度值显著增加。

Application of cutinase in polyester surface modification

Polyester fabrics present poor hydrophilic property. This research uses cutinase from H.insolens to modify the surface of polyester fabrics. The UV absorbance of the residual reaction liquid was evaluated and the treatment condition was determined based on the single-factor test. A suitable treatment condition for polyester fabrics was achieved under the cutinase concentration of 100 U/mL at 60 ℃ and pH 8.5 for 72 h. Under these conditions, Trition X-100 surfactant, with a dosage of 0.1%, was added to the reaction system, leading to significantly increase in the yield of cutinase-catalyzed hydrolysis of polyester fabrics. The type of product in the reaction residue, the hydrophilicity and dyeing properties of the treated and untreated fabric were measured, and the surface morphology and surface chemical composition of polyester were characterized. The mechanism of enzymatic modification of polyester was proposed. The results show that two main products yield from cutinase hydrolysis of polyester, namely mono-terephthalic acid 2-hydroxyethyl ester (MHET) and terephthalic acid (TPA). The surface of the polyester fabric became rough and the contact angle of polyester fabric was reduced from 93.4° to 83.1°. The dyeing depth value of the methylene blue dyed polyester fabric was significantly increased after the cutinase treatment, and the strength of C=O and C—O bands in the infrared spectrum corresponding to ester bond of cutinase-treated polyester fabric was decreased. It is indicated that the cutinase is able to catalyze the hydrolysis of ester bond on the surface of the polyester fabric, thus effectively improving the hydrophilicity of the polyester fabric.