节点文献
棉织物多元羧酸DP整理
Durable Press Finishing of Cotton Fabrics with Polycarboxylic Acids
【作者】 赵敏;
【导师】 周翔;
【作者基本信息】 东华大学 , 纺织化学与染整工程, 2003, 博士
【摘要】 多元羧酸应用于防皱整理是近年来的一个研究热点。1,2,3,4—丁烷四羧酸(BTCA)的防皱整理效果很好,但价格偏高,影响推广应用。研究比较多的另外一个多元羧酸是柠檬酸(CA),它价格较低,但整理效果特别是耐洗性较差。不饱和二元羧酸马来酸(MA)和衣康酸(IA)在整理效果和经济效益方面具有实际应用的潜力,目前应用这类多元羧酸的防皱整理研究还不是很充分。本论文对MA/IA和MA的在位聚合整理以及聚马来酸(PMA)的合成和整理进行研究。 在MA/IA的在位聚合整理中,通过对单体摩尔比,单体、催化剂、引发剂浓度,预烘和焙烘条件等六个因素的考察,确定了MA/IA在位聚合-交联整理的基本应用工艺。将MA/IA和MA两种在位聚合-交联整理与CA的整理效果进行比较的结果表明,与常规整理方法相比,在位聚合整理确实能够提高整理品的强力保留值,且MA/IA的整理品在折皱回复角、强力保留和耐洗牢度三方面都具有较好的效果。汽蒸处理工艺与常规干态处理工艺对整理品回复角的影响表明,以汽蒸预烘代替干态预烘的效果要好于以汽蒸焙烘代替干态焙烘的效果,但与常规工艺的整理品相比,汽蒸预烘或汽蒸焙烘都并未能进一步提高在位聚合整理品的断裂强力保留值。 对在位聚合-交联整理所用的引发剂作了进一步的研究,结果表明,与单用过硫酸钾相比,采用氧化还原引发体系可以提高反应速率、降低反应温度,有助于提高整理品的强力保留值。 进一步研究了添加剂对整理品性能的影响,指出不同添加剂较适宜的用量范围,其中效果较好的有三乙醇胺(TEA)和多元醇类。以TEA为例,它可有效地提高整理品的强力保留值、白度和耐洗牢度等多项性能,是一种很理想的添加剂。为了分析TEA具有这种改善作用是否主要由其碱性引起,本文用氢氧化钠(NaOH)将整理液的pH值调至与添加有TEA的整理液相同,分别测定两种整理品上的酯键量及整理品的回复角和强力。所得结果表明,与加有NaOH的整理品相比,TEA整理品上的酯键量明显较高,而其回复角仅稍有增大,强力保留率提高了4个百分点,说明TEA整理品上的酯键量有一部分应是TEA分子中的经基与多元梭酸的梭基发生醋化反应而形成的,从而有利于三维弹性网络结构的形成,因此能够改善整理品的强力、耐洗牢度等性能。本文提出了强力损失因子BSLF这一指标,它表示织物的折皱回复角每提高1“时断裂强力损失的百分率。在对添加剂的效果进行研究时,发现BSLF能够用于判断添加剂对整理品强力损伤的影响情况。如果加入一定的添加剂,使BSLF的值明显降低,说明使用这种添加剂能够提高棉织物的断裂强力保留值。 研究还发现,M刀IA在位聚合整理品在初期洗涤过程中,整理品上游离梭基量的减少速度要大于酷键量的减少速度,说明洗涤初期发生单端结合的酷键的水解速度大于生成交联的酷键的水解速度,表现在M户以IA整理品具有较高的耐洗牢度,这与文献中所述BTCA的情况类似。 本文在确定基本应用工艺的基础上,还对MA/IA和MA两种在位聚合一交联整理中单体的聚合反应动力学及多元梭酸与纤维素大分子发生的酷化反应的动力学进行了研究,分别得到聚合反应和酷化反应的反应速率常数k、Arrhenius活化能E。、指数前因子A,从而计算出活化烩、活化嫡、活化Gibbs自由能等活化参数。从M刀IA和MA两种在位聚合一交联整理的反应动力学参数的差异,可以解释它们聚合反应和酷化反应进行的难易程度及整理品性能的不同。不同焙烘条件下整理品上的醋键量与折皱回复角、断裂强力保留率之间存在着良好的线性关系,为整理品性能的预测提供了可行性。此外,对一系列经不同条件处理的棉织物的红外光谱分析证实,聚合反应主要发生于烘干阶段,而酷化反应则发生于焙烘阶段。 为了进一步阐明在位聚合一交联整理的特点,本文对聚马来酸(P MA)的合成及整理进行了研究。通过对引发剂用量、反应温度和反应时间等因素的分析,确定了在本文研究范围内比较适宜的合成工艺;随后通过正交试验设计法确定了PMA单独使用、或PMA与CA混合使用的整理工艺。整理品的性能比较结果表明PMA整理品在强力和耐洗牢度等方面都不如M刀IA在位聚合一交联的整理品,再次说明了在位聚合一交联整理的优越性。 最后对M刀IA和PMA整理品的性能进行了综合分析,如物理机械性能、白度、毛细管效应、耐洗性等。整理品的断裂伸长曲线表明,整理品的断裂强力和断裂伸长率都明显降低。经过家庭洗涤后整理品的强力有一定程度的恢复,且数据拟合结果也说明强力与折皱回复角之间具有良好的线性关系,进一步表明交联是整理品强力损失的主要原因。通过数学推导将这一拟合直线的斜率与本文所子提出的强力损失因子BSLF联系起来,与直线斜率相比,BSLF这一因子计算较为简便快捷,可用于比较不同整理体系的强力损失程度。耐洗性能的比较表明,在所研究的范围内,M刀IA在位聚合一交联的整理品具有最好的耐洗牢度,其次为MA在位聚合一交联的整理品,PMA整理品的耐洗性较差。
【Abstract】 In this paper a detailed investigation was carried out to elucidate the effects of a non-formaldehyde polymerization-crosslinking treatment on the performance properties of 100% cotton fabrics. The fabric samples were treated with unsaturated dicarboxylic acid(s) (maleic acid (MA) and/or itaconic acid (IA)) in the presence of polymerization initiator and esterification catalyst. It is believed that long chain polycarboxylic acids can be produced by addition polymerization of monomer(s). Subsequently these newly formed polymers react with cotton cellulose at elevated temperature to form ester-type crosslinks with cellulose molecules to obtain the finishing effects.The effects of parameters such as monomer and initiator concentration, temperature and duration of drying and curing, and catalyst concentration were explored in this study. The treated fabric samples were evaluated in terms of retention of mechanical properties and improvement of wrinkle recovery angle to determine a suitable finishing process. Performances of cotton fabrics treated with MA/IA or MA polymerization-crosslinking method were compared to those treated with citric acid (CA). The results demonstrate that the system of a 1:1 molar ratio of MA and IA substantially increases wrinkle resistance while maintaining much improved strength retention of the treated fabric. The finishing effects of steam process were compared with the conventional process, and it appears that steam drying or curing does not contribute to the improvement of the fabric strength retention.The strength retention of the treated fabric can be further improved when moderate amount of reducing agent is added in the finishing bath to form an oxidizing-reducing system with the initiator. This is probably due to the factor that reaction rate can be improved by the oxidizing-reducing system.The study has also examined the effect of using various potential additives. The performance of treated fabrics can be further increased by adding moderate amount of triethanolamine (TEA) or polyols. Take TEA as an example, strength retention, durability on washing and whiteness of the treated fabric can all be improved. To investigate the probable cause of such improvement, cotton fabrics were treated with two finishing baths containing TEA or NaOH, respectively. The introduction of NaOH in the treatment bath was to adjust the pH value to the same as the bathcontaining TEA. The amount of ester-linkages formed on treated fabrics, the wrinkle recovery angle and tensile strength retention of treated fabrics were determined and compared. For the TEA-treated samples, the ester-linkage content was greatly improved, while the wrinkle recovery angle only slightly increased. Thus, it seems that hydroxyl groups of TEA react with carboxyl groups to form ester-linkages and even flexible network structure, which leading to the improvement of the strength retention and washing durability of treated fabrics.The home laundering tests show that for the MA/IA-treated fabrics, the amount of free carboxyl groups decreases more greatly than the ester-linkages. Therefore, it can be concluded that ester-attachments were more ready to hydrolysis than ester-crosslinkings, and that MA/IA-treated fabrics exhibit good washing durability. The results are similar to the case of BTCA in literature.The reaction kinetics and activation parameters of MA/IA or MA in-situ polymerization-crosslinking treatment have been determined by measuring the unreacted portion, respectively. Values for Arrhenius energy (Ea) and rate constant (k) can be used to explain the performances of fabrics treated with different finishing baths. For both polymerization and esterification, the activation energy for MA treatment is higher than that for MA/IA. Enthalpies, entropies, and Gibbs free energies of activation of the systems were also calculated. In addition, infrared spectrum analysis was utilized to extrapolate during which stage the reaction occurs according to the changes in the functional groups in cellulose.To further elu
【Key words】 cotton; cellulose; polycarboxylic acid; durable press; polymerization; esterification; crosslinking;
- 【网络出版投稿人】 东华大学 【网络出版年期】2003年 04期
- 【分类号】TS195
- 【被引频次】3
- 【下载频次】424