Control of thermal expansion coefficient of materials is widely needed in the industrial field. Many materials with negative thermal expansion coefficient have been reported. These materials are useful for the secondary phase of composites, because small amounts can effectively offset thermal expansion of the matrix. Materials having a negative coefficient of thermal expansion are classified by their mechanism, i.e. phase transition and framework structure. Composites containing materials with negative thermal expansion coefficient have been reported. Their thermal expansion coefficient was between the value predicted by rule of mixture and Tuner equation. Discussion of interaction of the interface between the filler and the matrix is expected as a future challenge because prediction of the accurate value is difficult.
A nanoparticle is a functional material that can afford high functionalization due to the high surface area and simple surface modification. Furthermore, it can be a fundamental component to develop nanodevices by the bottom-up approach based on its uniform sphere shape. Recently, nanoparticles with opto-electrial properties have been attracted much attention for their potential for realizing the further growth of electronics. To date, we have been working on the opto-electrical functionalization of organic nanoparticles in terms of the variety of material design, facile tuning of material properties, and high processability. Herein, we report our recent study on the one-pot synthesis of opto-electrical core-shell nanoparticles using well-defined block copolymers prepared by controlled radical polymerization.
Concrete is a key material that supports social infrastructure. It's value and function are greatly enhanced by interfacial scientific action of agents added in small amounts. In this paper, the use of low molecular weight surfactant, like “AE agent (Air Entraining agent)”, which improves handling and durability of concrete, as well as “Rheology Modifier”, which adds unique viscoelasticity to slurry, will be shown.
The US Toxic Substances Control Act (TSCA) was amended in June last year (2016). Under the revision of the global chemical substance management policy, the revised law improved some of the problems of TSCA that had been pointed out in the past.
Under the revised law, amendments were made to strengthen the information gathering capability of the Environmental Protection Agency (EPA), the competent authority, and to change the triggering requirements of regulatory measures for harmful chemical substances, so that regulatory measures based on TSCA can be mobilized. Regarding the management of existing chemical substances pending issue of a new method was adopted to carry out inspection of safety according to priority. Furthermore, it is stipulated by the provisions of the law to utilize the TSCA Workplan, a voluntary chemical safety check program.
In this paper, I will explain the factors of the TSCA reform focusing on the above issues and points of revision as simply as possible.