两种橡胶/有机累托石纳米复合材料的结构与性能

Structure and Properties of two kinds of Organic-Rectorite/Rubber Nanocomposites

比较了用熔体法制备的有机累托石(OR)/丁苯橡胶(SBR)以及有机累托石(OR)/天然橡胶(NR)2种纳米复合材料的结构与性能。TEM和XRD对材料的分析显示,由于橡胶基体的性质差异,OR/SBR为典型的插层型结构,而OR/NR为插层型和部分剥离型混合结构。应力应变行为的研究表明,随着OR用量的增加,OR/SBR的拉伸强度和拉断伸长率均增大,这主要是分子链滑移和填料的取向造成的。对于拉伸结晶型橡胶NR,由于部分剥离型填料的增强作用,NR的定伸应力随填料用量的增加而逐渐提高。由于对结晶的阻碍作用,当OR用量为20份时,OR/NR的拉伸强度有所降低。纳米累托石的加入可以显著提高SBR和NR的硬度和撕裂强度。热失重分析表明,OR/橡胶纳米复合材料与相应的纯橡胶相比,热稳定性提高,在NR体系中更为显著。

Two rubber-based nanocomposites, natural rubber （NR） and styrene-butadiene rubber （SBR） matrixes, were prepared with organic rectorite（OR） by melt blending. X-ray diffraction（XRD） revealed that the OR/SBR nanocomposites exhibited a well-ordered intercalated structure; in the case of the NR/OR nanocomposite, it exhibited an intermediate intercalated and partial exfoliated structure. These results were in well agreement with transmission electron microscopy （TEM） observations. The tensile strength and the elongation at break of OR/SBR increased with the OR mass fraction increasing. For the strain-induced crystallization NR, the partial exfoliated OR efficiently improved the modulus of NR/OR nanocomposite, and however, its hindrance on NR crystallization during the tensile process might be the main reason for the decrease in tensile strength of OR/NR loading 20phr. The introduction of OR into SBR and NR enhanced their hardness and tear strength. TG analysis displayed the thermal stability of OR/SBR and OR/NR nanocomposites were enhanced in comparison with that of the corresponding pure rubber, especially in the NR matrix.