Department of New Architectures in Materials Chemistry, Instituto de Ciencia de Materiales de Madrid CSIC, Calle Sor Juana Inés de la Cruz 3, Madrid, Spain.
Phys Chem Chem Phys. 2011 Mar 21;13(11):4901-10. doi: 10.1039/c0cp00882f. Epub 2010 Nov 23.
This work describes a systematic study of gelatin-sepiolite structural bionanocomposites to show how the renaturation level of the biopolymer is highly dependent on the type of mineral particle used. The aim of the work is to prove that chemical interactions between both components (hydrogen and covalent bonding) determine the organization level of the biopolymer which in turn results in drastic differences in the elastic properties of the prepared bionanocomposites. To assess this, several systematic modifications were introduced into the silicate structure and surface, generating four derivatives. Two derivatives prepared by thermal treatments, monohydrated sepiolite and protoenstatite, and two chemically modified sepiolites, amino and epoxy terminated, were prepared and used as the inorganic (or hybrid) phase in the bionanocomposites. The thermal and chemical modifications performed on the sepiolite surface induced a dramatic decrease in the renaturation level as determined by DSC and FTIR techniques. On the other hand, untreated sepiolite induced a higher renaturation level in the polypeptide, probably due to the alignment of the collagen-like triple helix along sepiolite external surface channels. The measured mechanical properties of the studied compositions confirm that the renaturation level of gelatin is a key factor in understanding the elastic properties of bionanocomposites. These results suggest that mineral particles introduced in the polypeptide matrix provide an effective control over the matrix crystallinity giving rise to tunable mechanical properties of the final bionanocomposite.
这项工作描述了对明胶-海泡石结构生物纳米复合材料的系统研究，以展示生物聚合物的复性水平如何高度依赖于所使用的矿物颗粒类型。这项工作的目的是证明两者之间的化学相互作用（氢键和共价键）决定了生物聚合物的组织水平，这反过来又导致了所制备的生物纳米复合材料的弹性性质的巨大差异。为了评估这一点，对硅酸盐结构和表面进行了几次系统的修饰，生成了四个衍生物。通过热处理制备的两种衍生物，一水合海泡石和原顽火辉石，以及两种化学修饰的海泡石，氨基和环氧封端的，被制备并用作生物纳米复合材料中的无机（或杂化）相。在海泡石表面进行的热和化学修饰导致复性水平急剧下降，这可以通过 DSC 和 FTIR 技术来确定。另一方面，未处理的海泡石在多肽中诱导了更高的复性水平，这可能是由于胶原样三螺旋沿着海泡石外表面通道排列所致。所研究的组合物的力学性能测量结果证实，明胶的复性水平是理解生物纳米复合材料弹性性质的关键因素。这些结果表明，引入多肽基质中的矿物颗粒提供了对基质结晶度的有效控制，从而产生最终生物纳米复合材料的可调机械性能。
