Nuvoli Daniele, Alzari Valeria, Pojman John A, Sanna Vanna, Ruiu Andrea, Sanna Davide, Malucelli Giulio, Mariani Alberto
Dipartimento di Chimica e Farmacia, Università di Sassari , Local INSTM Unit, Via Vienna 2, 07100 Sassari, Italy.
ACS Appl Mater Interfaces. 2015 Feb 18;7(6):3600-6. doi: 10.1021/am507725k. Epub 2015 Feb 3.
Functionally gradient materials (FGMs) with gradual and continuous changes of their properties in one or more dimensions are useful in a wide range of applications. However, obtaining such materials with accurate control of the gradient, especially when the gradient is nonlinear, is not easy. In this work, frontal polymerization (FP) was exploited to synthesize polymeric FGMs. We demonstrated that the use of ascending FP with continuous feeding of monomers with computer-controlled peristaltic pumps provided an excellent method for the preparation of functionally gradient materials with programmed gradients. To test the effectiveness of the method, copolymers made from triethylene glycol dimethacrylate/hexyl methacrylate with linear and hyperbolic gradient in composition were synthesized. Differential scanning calorimetry (DSC), Shore A hardness measurements, compression tests, and swelling studies were performed along the length of the materials to assess the relationship between the gradients and the material properties. Glass transition temperatures, determined by DSC, showed a linear dependence on the composition and were in agreement with theoretical values. The other properties showed different and specific behaviors as a function of the compositional gradient.
功能梯度材料（FGMs）在一个或多个维度上具有逐渐且连续变化的特性，在广泛的应用中很有用。然而，要精确控制梯度来获得这种材料并不容易，尤其是当梯度是非线性的时候。在这项工作中，利用前沿聚合（FP）来合成聚合物功能梯度材料。我们证明，使用上升前沿聚合并通过计算机控制的蠕动泵连续输送单体，为制备具有编程梯度的功能梯度材料提供了一种出色的方法。为了测试该方法的有效性，合成了由二缩三乙二醇二甲基丙烯酸酯/甲基丙烯酸己酯制成的具有线性和双曲线组成梯度的共聚物。沿着材料的长度进行差示扫描量热法（DSC）、邵氏A硬度测量、压缩试验和溶胀研究，以评估梯度与材料性能之间的关系。通过DSC测定的玻璃化转变温度显示出与组成呈线性关系，并且与理论值一致。其他性能则随着组成梯度呈现出不同的特定行为。
