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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.

The following article reports on the use of PUR (polyurethane) systems for the building industry and discusses the choice of PUR raw materials available with particular reference to the surface treatment of concrete facades. One‐pack polyurethanes are used principally for impregnating concrete surfaces and solvent‐free PUR coatings can be made so elastic that cracks in concrete structural components can be bridged. Knifing polyurethane products can be used in the laying of ceramic tiles. Joint sealants can be produced either from two‐pack products or from blocked isocyanate prepolymers, which react with ketimines only in the presence of atmospheric moisture. Epoxy resin coatings are elasticised by blocked prepolymers. Statistics show that 30 per cent of plastics produced in the Federal Republic of Germany are used in the building industry. Nearly all plastics and paint binders are included in this figure. Polyurethane raw materials have also been used for many years. Apart from PUR insulating materials, polyurethanes are used in interior decoration as parquet floor varnishes, where abrasion resistance, flexibility and resistance to chemicals are required.

The purpose of this paper is to synthesise a novel wet-rubbing fastness improver with diphenylmethane diisocyanate (MDI), polyethylene glycol (PEG), dimethylol propionic acid (DMPA), diethylenetriamine and epichlorohydrin.

The synthetic reaction was carried out through three steps: pre-polymerising, chain-extending and chemically modifying. The influence of monomers dosage and ratio, temperature and time on reaction system and wet-rubbing fastness of reactive dye is studied. The target product was characterised by transform infrared spectroscopy analysis.

The optimum synthetic process condition of the improver is as follows: reaction temperature 100°C; pre-polymering time 2.5 hours with R value [n(NCO): n(OH)] 1.35 and DMPA 7 per cent (on percentage of total moles of MDI and PEG); chain-extending time 30 minutes with diethylenetriamine 1.5 per cent (on percentage of total moles of MDI and PEG); modifying time 2 hours with diethylenetriamine : epichlorohydrin = 1:2 (mole ratio).

The synthetic product is a three-functions-in-one (filming, salt-forming and cross-linking) wet-rubbing fastness improver which can obviously improve the wet-rubbing fastness of reactive dyes from Grade 2-3 to Grade 4.

The wet-rubbing fastness improver is novel and could find numerous applications in dyeing and finishing.

In the sector of light‐stable, two‐pack polyurethane coatings (high‐solids coatings) new binder systems were developed during the last few years. When polyisocyanate adducts suitable for low‐solvent, two‐pack polyurethane coatings are to be formulated, it is necessary to adjust the functionality, the molecular weight and the starting components appropriately to one another. This also applies to the polyhydroxy compounds used as co‐reactants. The various parameters for controlling the polymer properties are discussed.

Polyurethane, abbreviated to PUR according to DIN 7728 and ISO /DR 1252, is the term given to a group of plastics produced from polyisocyanates and polyalcohols and having the following chemical groupings as the characteristic connecting link:

The purpose of this work was to prepare a catalyst-free microcapsules as self-healing agent in an automotive clearcoat to improve the scratch resistance of coatings.

In this research, microcapsule with isophorone diisocyanate (IDPI) core and polyurethane shell were prepared and used in self-healing coatings. Microcapsules synthesised were characterised by thermal gravimeter and infrared spectra. The microcapsules were dispersed in an acrylic-melamine clearcoat, and the scratch resistance was evaluated.

The triplex product and the formed polyurethane bonds were confirmed by thermal gravimeter and infrared spectra. In addition, smooth spherical particles with a diameter of 1.5 to 1.7 micronmeters were observed by a scanning electron microscope. The microcapsules dispersed in an acrylic-melamine clearcoat increased the scratch resistance of coatings. Also, the self-healing feature of those coatings was proved.

The size of microcapsules can affect its dispersion in the clearcoat and consequently affect the properties of the cured films.

The self-healing coatings are interested for many industries such as building and automotive industries. The reported data can be used by the formulators working in the R & D departments.

Self-healing systems are considered as one of the smart coatings. Therefore, the developing of its knowledge can help to extend its usage to different applications.

The application of microcapsules in the coating as healing agents is a great challenge, which has been hardly investigated so far. In the current research, the effect of polyurethane-IDPI microcapsules in an automotive clearcoat as a self-healing coating was investigated.

The paper's aim is to synthesise ultraviolet (UV) curable polyurethane acrylate based on polyester polyol and to study change in its mechanical, chemical, optical and weather resistance properties with varying amount of nanosilica. It also seeks to determine its optimum loading levels for property maximisation.

New UV curable polyurethane acrylate has been synthesised using polyester polyol, blend of isophorone diisocyanate and toluene diisocyanate and hydroxyl ethyl acrylate. This resin was incorporated with nanosilica (1‐3 per cent) on the basis of total solids. The newly synthesised material was characterised by fourier transform infrared spectroscopy, gel permeation chromatography, X‐ray diffraction and scanning electron microscopy. The mechanical, chemical and optical properties of the coating films were studied and compared.

The hardness, tensile strength and abrasion resistance show significant enhancement with increasing amount of nanosilica. It is also found that UV cured polyurethane acrylate nanocoating exhibited improved weather resistance. The optimum concentration of nanosilica for better performance is found to be 3 per cent of total solids. The improvement is the result of inherent nature of nanosilica.

Nanosilica used in present context is having 10 nm mean diameter and near about 600 m²/g surface area. Nanosilica having different particle size, surface area and surface modification can be used to improve more specific properties.

Addition of nanosilica particles to polyurethane acrylate coating is a simple and inexpensive method resulting in phenomenal increase in properties.

The new organic‐inorganic hybrid nanocoating with improved weather resistance was synthesised. These coatings could find applications in demanding fields such as automotive topcoats.

Urethane Acrylate Oligomer with 100% solids was synthesised and characterised in order to study the application in electron beam curing with varying ratio of Trimethylol propane triacrylate (TMPTA). The purpose of this paper is to study effect of TMPTA addition on the crosslink density and different coating properties.

Polyester polyol was synthesised by reacting single diacid, adipic acid (AA), with Pentaerythritol (PENTA) and 1,6‐hexanediol (HD). Further, Urethane acrylate resin was synthesised by using Isophorone diisocyanate (IPDI), hydroxy ethyl acrylate (HEA) and Polyester polyol. The polyester polyol and urethane acrylate oligomer were characterised by 1H NMR, 13C NMR, FTIR and GPC. Further, TMPTA was added as a crosslinker to the urethane acrylate oligomer and cured by electron beam radiation. The cured UA films having varying concentration of TMPTA were employed to evaluate thermal property, contact angle analysis, mechanical and chemical properties.

The obtained results showed improvement in their chemical properties, mechanical properties, thermal properties and water contact angle at 20% of TMPTA iconcentration. The TMPTA also reduced the dose required for the curing.

The resin can be synthesised from different isocyanates as TDI, MDI and HMDI, etc. The study can also be done with different multi or mono functional monomers such as methacrylate, hexanediol diacrylate, ethylene glycol diacrylate, etc.

The paper provides the better solution to reduce the cost of the electron beam radiation required for the curing.

The method presented in the paper could be very useful for controlling environmental pollution; as the conventional method of curing releases volatile organic compounds (VOC).

In this paper, urethane acrylate and TMTPA cured with electron beam are shown to offer good coating properties. A high‐solid urethane acrylate coating would find numerous industrial applications in surface coatings.

In this study, it is aimed to synthesize ultraviolet (UV)-curable water-borne polyurethane acrylate (WPUA) binders using different types of polyols (poly (propylene glycol), PPG₁₀₀₀ and PPG₂₀₀₀ and poly (ethylene glycol), PEG₁₀₀₀ and PEG₂₀₀₀) at different molecular weights, DMPA (2,2-bis(hydroxymethyl) propionic acid) at different amounts and isophorone diisocyanate (IPDI) and use for pigment printing on synthetic leather.

UV-cured films were characterized by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimeter (DSC). The effect of binder structure on printing performance was determined with hardness, crock fastness, abrasion resistance and color measurements.

The highest abrasion resistance (60,000 cycles) and crock fastness values (dry crock and wet crock: 3/4) were obtained with binder PEG-C synthesized with PEG₂₀₀₀ and lower DMPA amount of 4.89 wt%; however, PEG-C binder showed lower hardness values. Due to lower urethane groups in PEG-C binder, more flexible films were obtained which imparted good adhesion property to printing film. Synthesized binders provided lower crock fastness and abrasion resistance properties than commercial WPUA binder.

Pigmented formulations including UV-curable water-borne synthesized PUA binder were developed and for the first time applied onto synthetic leather using screen printing method. Within this context, a new environmentally friendly printing method was proposed in this study including binder synthesis in the preparation of printing formulations.