Novel functional materials from rice husk ash (RHA) silica for concrete and polymer composites

稻壳灰(RHA)二氧化硅混凝土及聚合物复合材料新型功能材料 提出的研究项目旨在开发应用于混凝土和聚合物复合材料的新型功能材料。新材料将来自一种广泛可用的可再生矿产资源：从稻壳燃烧残渣中获得的多孔二氧化硅，通常被称为“稻壳灰”(RHA)。众所周知，RHA对混凝土的强度和耐久性是有益的，它作为聚合物复合材料的填料的潜在用途也得到了证明。然而，到目前为止，实际困难极大地限制了它们在此类应用中的使用，因此需要新的方法来使RHA更有价值，并对从业者更友好。为了实现这一总体目标，RHA将通过各种化学方法进行升级和修改。 对于混凝土应用，我们将制定策略，将某些类型的外加剂(例如增塑剂、减缩剂、防腐剂)“固定”在RHA的气孔中，以便在混凝土搅拌、水化、凝结和硬化的不同阶段及时释放。为复合材料设想的RHA功能在原理上是相似的，但将被开发来缓解特定的问题，通常是在均质处理造粒的固体聚合物和液体组件(加工助剂、增塑剂)方面的困难，或者需要随时间释放改善特定性能的添加剂，即表面光洁度、表面导电性等。

Novel functional materials from rice husk ash (RHA) silica for concrete and polymer composites The proposed research project aims to develop new functional materials for application in concrete and polymer composites. The new materials will be derived from a widely available renewable mineral resources: porous silica obtained from the combustion residue of rice hull, and generally referred to as «rice husk ash» (RHA). RHA is already known to be beneficial to the strength and durability of concrete, and its potential use as a filler in polymer composites has also been demonstrated. To date however, practical difficulties have greatly limited their use in such applications, so new approaches are needed to make RHA more valuable and «user-friendly» to practitioners To achieve this general goal, the RHA will be upgraded and modified through various chemical approaches. For concrete application, we will develop strategies for «fixing» certain types of admixtures (e.g., plasticizers, shrinkage control agents, corrosion inhibitors) in the pores of the RHA for timely release during different phases of concrete mixing, hydration, setting and hardening. The RHA functions envisaged for composite materials are similar in principle, but will be developed to alleviate specific problems, typically difficulties in homogeneously processing pelletized solid polymers and liquid components (processing aids, plasticizers), or the necessity for time-dependent release of additives which improve specific properties, i.e., surface finish, surface conductivity, etc.