Metal and metal sulfide clusters embedded in polymeric matrices represents a novel nanostructured material class. These materials combine optical transparency to magnetism, luminescence, UV-visible absorption, thermochromism, etc. leaving to unique functional materials that can be conveniently exploited for a number of applications in different technological fields. A really effective synthesis route for these materials is represented by the thermal decomposition of mercaptide molecules dissolved in polymer. Mercaptides can be dissolved/dispersed in polymers and thermally degraded at temperatures compatible with polymer stability (100°-250°C), generating metal atoms or metal sulfide molecules that leave to very small nanoparticles by clustering. Mercaptide synthesis, blending with polymers, and thermal decomposition are quite simple and general operations, consequently this approach can be easily applied for the preparation of a variety of nanocomposite systems. In this review, we present some fundamental aspects related to the chemistry of mercaptides (synthesis), the calorimetric study of their thermolysis process, the main techniques for nanocomposite characterization, and a short description of material applications. This article also includes recent patent coverage.
Glass is a material that is widely used in various fields of techniques and engineering (optics, electric devices, ware, medicine, etc.) due to a unique combination of properties, many of them being possible to vary in wide ranges depending on chemical composition. For this reason chemical compositions of glasses of various usage are widely patented. In the paper, the history of patenting the glass compositions since 1907 as well as present-day trends of development of new glasses are analyzed by using the database SciGlass IP containing the data about 100,000+ patents and patent applications published worldwide. Todays challenges during the development of new glass compositions and possible solutions are characterized.
The fabrication of liquid crystal devices requires a reproducible and accurate method of aligning the LC on the surface of the electrodes. Rubbed polyimide surfaces have been successfully employed but suffer disadvantages. Recent developments in technology have seen new methods based on ion and plasma bombardment, UV exposure and electron irradiation. In addition, there has been much activity in achieving LC alignment through doping of the LC itself with suitable agents. Here, we review the recent developments in LC alignment technology and the patent literature in this area.
The synthetic polymer, polyacrylamide derived from acrylamide monomer, was originally introduced for use as a support matrix for electrophoresis in 1959. Later, because of its applicability and economy, polyacrylamide has found widespread applications ranging from microanalysis to macro-fractionation for proteins, nucleic acid, and other biomolecules. On the other hand, recent years also witnessed increasing research interests in the potential of polyacrylamide acting as biomaterials. This review article will comprehensively present and discuss recent interesting patents classified according to the following highlights: (1) Enzyme immobilization within polyacrylamide gels; (2) Carriers for delivery of drugs and bioactive compounds; (3) Smart materials able to respond with stimulus; (4) Polyacrylamide-based matrices in extracorporeal toxin removal modalities; (5) Non-absorbable soft tissue fillers used for body contouring in reconstructive surgery or for cosmetic purposes. In summary, current researches and achievements of polyacrylamide have therefore well demonstrated its versatility and usefulness as biomaterials. Further developments of polyacrylamide-associated technologies will undoubtedly enhance the value and broaden the possibilities of applications of polyacrylamide in the field of biomaterials.
Advanced ceramic and metallic coatings for wear and corrosion protection of engineered structures applied by thermal spraying techniques have become a mainstay of surface engineering. Estimated global sales of thermally sprayed coatings are in the US$5 billion range per year, 50% of which are achieved by atmospheric plasma spraying. The development of suitable deposition equipment, sophisticated on-line process control, ease of application to complex surfaces, availability of a broad range of tailored feedstock materials, and sensitive characterization and quality assurance methods make novel surface coatings and their improved deposition techniques increasingly attractive. This review will cover patented progress in the field of wear- and corrosion-resistant coatings achieved during the past few years.
Continuous development of advanced technologies brings about the constant need for new materials with suitable properties to even stricter demands. A special interest has been given to the development of inorganic transparent materials, not only for optical and lighting applications, but also in the electronic, aerospace, civil construction and armour industries. The major motivations are generally weight reduction and enhancement of mechanical properties, also at high temperatures, while simultaneously keeping or, in some cases, increasing the optical transparency. A review of the latest industrial developments in the field of transparent inorganic materials is presented in this paper. Relevant patents disclosed for polycrystalline ceramics, glass-ceramics and composites, in which transparency is claimed as one of the main properties achieved, are described and discussed. Only fully inorganic materials have been considered, therefore, in the case of composite materials, laminate systems including polymeric layers (commonly used in armour applications or security glass) were not included in the review. Moreover, focus is on structural applications, while optical and telecommunication-related materials are not covered in detail.
The requirement for diverse applications such as digital video, interactive media etc. demands high storage densities, rapid data transfer rates, random access to data and removability of the storage media. The complete technology involves suitable recording medium and the processes for recording, post treatment and reading. The challenge in the development of holographic storage system is the availability of appropriate recording medium which shows maximum refractive index change on irradiation. In this article, attempt has been made to discuss the important disclosure of patents made during rapid development of the holographic recording medium. Silver halide emulsions to variety of photopolymers are developed to achieve minimum polymer film shrinkage, minimum post processing and multiple writing. All types of polymer based mediums are incorporated in this article. Few discussions are divided into subsections. It has generally been observed that acrylates, acrylamide, carbazolyl-, fluorenyl-, anthracenyl- containing monomers are common monomers and polymethyl methacrylates, polyvinyl alcohols, epoxy resin, sol-gel to polyelectrolytes are the common matrix resin. A recent addition is the nanoparticles in the composition to improve the diffraction efficiency and hologram stability. A different class of photopolymer called photorefractive polymer is also reported. Liquid crystalline polymer is photopolymer which provides erasable holographic media. Claims chosen are mostly from US patents. Some other literatures are also included as demanded by the discussion. The important features of the medium used in patents are highlighted. The details about performance, as claimed in certain patents, are incorporated. Rapid developments are observed in the subject.