Nasrollah Gavgani Jaber, Goharpey Fatemeh, Velankar Sachin
Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O.Box-15875-4413, Tehran, Iran.
Department of Chemical Engineering, Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
Soft Matter. 2021 Nov 3;17(42):9670-9681. doi: 10.1039/d1sm01057c.
We investigate the interfacial compatibilization effect of reduced octadecylamine-functionalized graphene oxide (ODA-GO) on the morphological and rheological properties of immiscible homopolymer blends of polydimethylsiloxane (PDMS) and polyisoprene (PI). We prepared droplet-matrix blends with a PI : PDMS ratio of 30 : 70 or 70 : 30 and interfacially localized ODA-GO stabilizer loadings from 0.1% to 1%. Blends were examined by optical microscopy and rheometry. Both blends show typical droplet-matrix morphology with stabilized round drops that do not stick together. With the addition of ODA-GO, smaller drops were observed in PI-continuous blends as compared to the PDMS-continuous blends suggesting that the effects of particles are not symmetric in the two cases. At sufficiently high ODA-GO loadings, flow-induced coalescence is suppressed almost completely. Dynamic oscillatory rheology broadly confirms the morphological observations. Specifically, all the blends show an interfacial relaxation process that is distinct from the bulk viscoelasticity, and the dependence of this process on GO content and flow conditions confirms the compatibilizing effect of the ODA-GO. This work provides a strategy for interfacially-compatibilizated polymer blends with specific properties for practical applications.
我们研究了还原的十八烷基胺功能化氧化石墨烯（ODA-GO）对聚二甲基硅氧烷（PDMS）和聚异戊二烯（PI）不相容均聚物共混物的形态和流变性能的界面增容作用。我们制备了PI与PDMS比例为30∶70或70∶30且界面局部ODA-GO稳定剂负载量为0.1%至1%的液滴-基体共混物。通过光学显微镜和流变学对共混物进行了研究。两种共混物均呈现典型的液滴-基体形态，其中稳定的圆形液滴不会粘在一起。与PDMS连续相共混物相比，在PI连续相共混物中加入ODA-GO后观察到更小的液滴，这表明在两种情况下颗粒的作用并不对称。在足够高的ODA-GO负载量下，流动诱导聚并几乎完全受到抑制。动态振荡流变学大致证实了形态学观察结果。具体而言，所有共混物均显示出一个与本体粘弹性不同的界面松弛过程，并且该过程对氧化石墨烯含量和流动条件的依赖性证实了ODA-GO的增容作用。这项工作为具有特定性能的界面增容聚合物共混物提供了一种用于实际应用的策略。
