Water-sorption properties of poly(ε-lysine): Carboxymethyl cellulose (CMC) dietary complex films
Water-sorption properties of poly(ε-lysine): Carboxymethyl cellulose (CMC) dietary complex films
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聚（ε-赖氨酸）的吸水特性：羧甲基纤维素（CMC）膳食复合膜
DOI：
10.1002/app.1994.070540111
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
T. Nakajima
中科院分区：
文献类型：
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作者：
T. Ichikawa;Y. Mitsumura;T. Nakajima
为探讨超吸附材料在食品工业中的应用，以聚赖氨酸（PEL）和羧甲基纤维素（CMC）为原料，采用溶剂浇铸法制备了聚离子复合膜，研究了其吸水性能和水凝胶的一些物理性能。三个CMC样品具有不同的取代度（DS）和分子量（MW），以显示各种吸水行为和物理性能。PEL/CMC的比例从10/90变更为50/50。当PEL与CMC形成的复合物具有较低的取代度和适当的分子量时，当PEL/CMC的比例较低时，可获得良好的膜在水中的溶胀。这表明CMC中的羧基不容易解离，并且阳离子和阴离子相互作用的强度影响膜溶胀。与此观点一致，电解质的加入显著降低了膜溶胀。非电解质如蔗糖或尿素没有影响。红外光谱和核磁共振谱表明，在聚电解质的离子基团的一部分相互作用。复合干膜的拉伸模量随PEL含量的增加而线性下降。溶胀膜的压缩模量既不受溶胀度也不受CMC分子量的影响。CMC的DS值越低，压缩模量越高。我们还研究了复合膜中聚合物组分的刚性与非冻结结合水的比例之间的关系。在丙酮-水或乙醇-水混合溶剂中溶胀时，聚合物凝胶在丙酮或乙醇浓度约为20 mol %时发生膨胀-收缩转变。PEL/CMC由线性聚阴离子多肽和阳离子环链组成，其总体特征使人联想到聚阳离子壳聚糖和聚阴离子聚谷氨酸。John Wiley & Sons，Inc.
To investigate the application of supersorbing materials in the food industry, the water sorption of polyion complex films, prepared by solvent-casting from poly(ϵ-lysine) (PEL) and carboxymethyl cellulose (CMC), were examined and some physical properties of the hydrogels were studied. Three CMC samples having various degrees of substitution (DS) and molecular weights (MW) were applied to show a variety of water-sorption behavior and physical properties. The ratio of PEL/CMC was changed from 10/90 to 50/50. Good film swelling in water was achieved when the complex was made from PEL and CMC with a low DS and an appropriate molecular weight, and when the PEL/CMC ratio was low. This indicated that the carboxyl groups in the CMC are not readily dissociated, and that the strength of cationic and anionic interactions affects the film swelling. In line with this view, the addition of electrolytes markedly lowered the film swelling. Nonelectrolytes such as sucrose or urea had no effect. IR and NMR spectra showed that a fraction of the ionic groups in the polyelectrolytes interact. Tensile moduli of complex dry films decreased linearly as the PEL content increased. Compressive moduli of swollen films were affected by neither the degree of swelling nor the molecular weights of CMC. The lower the DS values of CMC, the higher the compressive moduli were. We also examined the relation between the rigidity of polymer component and the ratio of nonfreezable bound water in complex films. On swelling in acetone–water or ethanol–water mixed solvent, expansion–shrinkage transition of the polymer gels occurred at about 20 mol % acetone or ethanol concentrations for every complex film. The overall characterstics of PEL/CMC consisting of a linear polyanionic polypeptide and a chain of cationic rings are reminiscent of polycationic chitosan and polyanionic polyglutamic acid. © 1994 John Wiley & Sons, Inc.