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The purpose of this paper is to synthesize and characterize a series of alicyclic two-component waterborne polyurethane (2K-WPU) which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion.

The appearances of aqueous dispersions and 2K-WPU films were observed by photographs. The micromorphology of alicyclic polyisocyanate aqueous dispersion was examined by scanning electron microscopy (SEM). The molecule structures of WPU were studied by Fourier transform infrared (FTIR). The effect of NCO:OH molar ratio of two components and trimethylolpropane (TMP) content on the thermal stability, mechanical and water resistance properties of 2K-WPU films was studied.

It was found by SEM that alicyclic polyisocyanate particles in aqueous dispersion showed a kind of spherical particle appearance, in which hydrophobic polyisocyanate was encapsulated by hydrophilic ether linkages segment. FTIR showed that WPU was polymerized through mixture of polyisocyanate component and hydroxyl component and increasing NCO:OH molar ratio of two components from 1.1:1 to 1.5:1 had increased the content of urea, urethane and allophanate of 2K-WPU films. Increasing NCO:OH molar ratio had improved the mechanical and thermal properties of the 2K-WPU film, but the water resistance of the 2K-WPU film increased first and then weakened. Increasing TMP contents from 1 to 0.75 mol for 1:5 system had improved the mechanical, thermal and water resistance properties of the 2K-WPU film.

The investigation established a method to prepare alicyclic 2K-WPU which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion. The prepared 2K-WPU film could be applied in the field of waterborne surface coating, e.g. textile, wood and synthetic leather surfaces (Hasan et al., 2017; Akindoyo et al., 2016).

The paper established a method to synthesize alicyclic two-component 2K-WPU. The effect of NCO:OH molar ratio and TMP content on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

The purpose of this paper is to examine the preparation of asymmetric mixed esters of methylolcyclohexanols in order to decrease the pour point and increase the thermal stability of base oils.

The aldol condensation reaction of cyclohexanone with paraformaldehyde is modified to give mixture of alicyclic polyols. The obtained mixture was subsequently esterified by different pure and mixed linear mono carboxylic acids to give asymmetric mixture of esters of methylolcyclohexanols/ones.

The obtained base lubricants showed better wear preventive characteristcs (four‐ball rolling contact test) compared with previously reported and commercially available ester base lubricants.

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The obtained materials are slightly acidic and should be neutralized before use or formulation.

The paper presents a new process for obtaining synthetic ester base lubricants from mixed polyols of neo structure, which was obtained from aldol condensation reaction of cyclohexanone and paraformaldehyde, and linear aliphatic monocarboxylic acids. The key step in this process is modifying the reaction condition for obtaining mixture of polyols, and not pure 2,2,6,6‐tetramethylolcyclohexanol. This allows one to obtain asymmetrical and complex mixture of esterification products, which is favored in the production of synthetic ester base stocks, having excellent viscosity‐temperature properties, decreased pour point, and increased thermal stability. The synthesized ester base lubricants also show excellent viscosity‐temperature properties compared with ester base lubricants of the same family.

The RINGDOC database of Derwent Publications Ltd. is the world's most comprehensive database covering pharmaceutical literature. RINGDOC contains over 500,000 references from 1964 to date and is searched using two indexing systems. Codeless scanning is a system of searching keywords and the Ring Code system is a unique method of searching chemical substructures and biological activities. This paper looks briefly at the history and structure of the RINGDOC database and describes methods of searching it.

The purpose of this paper is to develop a flexible, as well as a rigid, polyurethane (PU) product using polyols derived from renewable resource for suitable application.

Cardanol is converted into corresponding glycidyl ether by reacting it with epichlorohydrin. The resulting glycidyl ether is hydrolysed to the corresponding diol in the presence of a heteropolyacid, which acted as a catalyst. The diol obtained is used for synthesising PU's by reacting it with various mole ratios of toluene diisocyanate (TDI) and isophorone diisocyanate (IPDI) and their physicomechanical, chemical and morphological properties are studied.

The polyol selected for the present paper has unique structural characteristics such as C15 chain length, which contributes to flexibility, and an aromatic ring, which imparts rigidity in the final application of resulting PU. By choosing optimum ratio of NCO/OH, it is possible to obtain a system, which can be used for the development of a flexible as well as a rigid polymer for suitable application.

The cardanol and dodecatungstosilic acid used are of a particular grade and of a particular manufacturer. Furthermore, it could be obtained from different sources and of different grades. The spectral studies done are purely qualitative. Gloss is tested for the samples at 600, whereas other angles can also be used.

The method developed provided a simple and practical solution to improve performance characteristics of PU resins, which also proves to be cost effective.

The PU product developed due to its enhanced coating properties can be used in various surface‐coating applications.

This concluding part reviews the actions of inhibitors to acidic, ammonical, organic, atmospheric and miscellaneous product corrosion on aluminium. The comprehensive reference list is also concluded.

The purpose of this paper is to analyze the network structure of technology in and between different fields, as well as the evolution of their relations.

Using the patent data in Derwent Innovation Index (DII) from 1991 to 2010, this paper analyzes the co-classification of Derwent Manual Code (DMC) of patents in all technology fields. Large-scaled co-classification matrices are employed to generate the DMC co-classification networks. In addition, analyses are pursued at different levels of aggregation in four five-year windows: 1991-1995, 1996-2000, 2001-2005 and 2006-2010. Using Girvan-Newman algorithm in the clustering process, the structure transformations over time are detected.

The paper identifies the key technological knowledge in certain fields and finds out how different technological fields are connected and integrated. What is more, the dynamic evolution between networks in different time periods reveals the trend of generic technology development in the macroscopic level.

The paper investigates a large quantity of data – all the patent data in DII from 1991 to 2010 in this paper. The paper applies Girvan-Newman algorithm in the co-classification analysis and uses co-classification networks to reveal technology network structures. Evolution coincident with the realistic technological shifts can be observed.

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

Zinc is one of the most important nonferrous metals and finds extensive use in metallic coatings. It is resistant to atmospheric attack and corrodes rapidly only in highly polluted air. It is resistant to most fresh waters but its resistance to sea water and to very soft water is lower. In many aerated hot waters, reversal of polarity between zinc and iron occurs at temperatures of 60°C or above. The corrosion products of zinc are readily soluble both in alkalis and acids and protect the metal surface only in neutral media. In neutral solutions, zinc is corroded mainly by oxygen depolarisation. The dissolution rate of zinc in acids is greatly affected by the over‐potential of hydrogen evolution at cathodic inclusions.

PART V Organic chemistry textbooks. Twenty textbooks of organic chemistry are considered in this part of the review and the organic sections of the syllabuses of three GCE Boards are analysed.

In recent years aluminium has become a very widely used material in the construction industry. Light weight, good corrosion resistance and ease of fabrication lends itself to a whole variety of end uses. Although the tendency for aluminium to oxidise in the atmosphere is itself a form of chemical “protection”, improvements in weather and chemical resistance can be gained from the use of a variety of surface coatings. These coating technologies are typically of the following types: polyvinylidine difluoride, water‐borne electro‐paint, conventional solvent‐based paints, powder coatings and anodising. The two most popular technologies in use today are: TGIC (Triglycidyl isocyanurate)/polyester powder coatings and polyvinylidine difluoride (PVDF) solvent‐based coatings. Coated aluminium has the added competition in the window frame and door frame market from uPVC. Only coated aluminium will be discussed in this paper.