Polymer and Biophysics Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Int J Biol Macromol. 2012 Apr 1;50(3):759-67. doi: 10.1016/j.ijbiomac.2011.11.028. Epub 2011 Dec 6.
Solution behaviour of hydroxyethyl cellulose (HEC) is reported in the polymer concentration range spanning over two decades (c=0.002-5% (w/v)). The results conclude the following: (i) dilute solution regime prevailed for c<0.2% (w/v), flexible HEC fibres of typical length ≈ 1 μm and persistence length ≈ 10 nm were found here, (ii) for 0.2<c<1% (w/v), a semidilute phase comprising soluble aggregates of hydrated HEC fibrils were observed with the material exhibiting viscoelastic behaviour and (iii) when 1<c<5% (w/v) the solution behaved with melt-like attributes with substantial embedded heterogeneity; viscous to elastic transition was observed in this region. Raman spectral, and DSC data indicated distinctive hydration of HEC fibres in the aforesaid concentration regimes. Cole-Cole plots revealed phase homogeneity and miscibility was limited to concentrations less than ~2% (w/v). For higher polymer concentrations, strong fibre-fibre interactions prevailed and samples became heterogeneous.
羟乙基纤维素（HEC）在跨越二十年的聚合物浓度范围内（c=0.002-5%（w/v））的溶液行为得到了报道。结果得出以下结论：（i）在 c<0.2%（w/v）时，存在稀溶液体系，这里发现了典型长度≈1μm 和持久长度≈10nm 的柔性 HEC 纤维，（ii）在 0.2<c<1%（w/v）时，观察到包含水合 HEC 原纤维的可溶性聚集体的半稀相，该材料表现出粘弹性行为，（iii）当 1<c<5%（w/v）时，溶液表现出类似熔体的特性，具有大量嵌入的不均匀性；在该区域观察到粘性到弹性的转变。拉曼光谱和 DSC 数据表明，在上述浓度范围内，HEC 纤维的水合作用具有独特性。Cole-Cole 图显示相均匀性，混溶性限于小于约 2%（w/v）的浓度。对于更高的聚合物浓度，纤维间的强烈相互作用占主导地位，样品变得不均匀。
