Synthesis of itaconic acid-based non-isocyanate polyurethane coating with excellent heat insulation and corrosion resistance

Preparation of ambient and UV curing non-isocyanate polyurethane (NIPU) coatings has been reported using a series of acetoacetylated non-isocyanate polyurethane (AA-NI-PUPO) oligomers. Synthesized oligomers were characterized using various techniques such as Fourier transform infrared and nuclear magnetic resonance spectroscopy. AA-NI-PUPOs showed significantly lower viscosity compared to their non-acetoacetylated counterparts. Ambient temperature-cured systems were formulated by mixing AA-NI-PUPOs and different primary amine compounds in stoichiometric proportions. Michael addition reaction of acrylates and AA-NI-PUPOs was initiated by UV curing using a photobase generator as the catalyst. NIPU coatings were studied for various thermo-mechanical properties and corrosion resistance. The selected UV-cured and ambient-cured samples showed instant and 1-h tack-free time, respectively. Results revealed that with proper selection of acetoacetylated resin and crosslinker type, coatings with properties comparable to conventional PU coatings could be formulated. Moreover, UV-curable coatings with up to 90 wt% solid could be formulated using conventional monomeric acrylates as a reactive diluent. The study demonstrates the feasibility of formulating solvent-free rapid ambient curing non-isocyanate polyurethane coatings.

Anti-corrosion non-isocyanate polyurethane polysiloxane organic/inorganic hybrid coatings

Polyurethane adhesives and coatings are widely used in Microelectronics and Photonics. The novel matrix of advanced nonisocyanate polyurethane (NIPU) coatings and adhesives are formed from two oligomers, one of them contains terminated cyclocarbonate groups (CC-oligomer), second terminated primary amines groups. As a result of forming an intramolecular bond and blockage of carbonyl oxygen it is considerably lowers the susceptibility of the whole urethane group to hydrolysis. We have elaborated a few technologies for the synthesis of CC-oligomers with different structures that give us possibility for preparing coatings from high elastic to very hard. By the data of IR-spectroscopy investigation the process of curing different CC-oligomers and primary amine oligomers was studied and give us all the needed information for many coating compositions' preparing according a lot of requests for a wide spectrum of industrial, decorative and another types of coatings. The chemical resistance and permeability of hybrid nonisocyanate polyurethane (HNIPU) coatings is 1.5-2.5 times better in comparison with conventional polyurethane coatings of the similar structure without the intermolecular hydrogen bond. Corrosive passive adhesives were prepared by a new method of their synthesis the method of multiplication. In the report will present the data of their testing by ASTM, DIN and BS. At the end of 2001 the industrial production of different nonisocyanate polyurethane systems for coating, adhesives and sealant will be established in the USA.

Synthesis and properties of poly(dimethylsiloxane)-based non-isocyanate polyurethanes coatings with good anti-smudge properties

Formulations of bio-based poly(cyclic carbonates) and amines using cooperative catalysis were studied to produce non-isocyanate polyurethanes (NIPUs). Concerns on the use of isocyanates as starting materials for polyurethanes (PUs) have risen due to their effects on human health after exposure and also because their synthesis involves the use of phosgene. Polyurethanes are highly versatile materials used in widespread industries such as automotive, building, construction, and packaging. They have also been used as flexible and rigid foams, adhesives, coatings, thermoplastic, or thermoset materials. Traditionally, PUs are synthesized from polyols and polyisocyanates. In order to circumvent the concerns, much research has been devoted to exploring alternative approaches to the synthesis of PUs. NIPU synthesis using cyclic carbonates and amines has gained popularity as one of the new approaches. In this study, novel bio-based resins were synthesized by converting epoxidized sucrose soyate into carbonated sucrose soyate (CSS) under supercritical conditions. Initial studies have shown promise in systems where CSS is crosslinked with multifunctional amines generating coatings with good solvent resistance. This work focused on studying the effect of catalysts and developing formulations of bio-based non-isocyanate polyurethane coatings.

Synthesis and properties of POSS-containing gallic acid-based non-isocyanate polyurethanes coatings

Synthesis, modification and properties of rosin-based non-isocyanate polyurethanes coatings

Proton nuclear magnetic resonance studies on glutaminebinding protein from Escherichia coli: Formation of intermolecular and intramolecular hydrogen bonds upon ligand binding

Crosslinked succinic acid based non-isocyanate polyurethanes for corrosion resistant protective coatings

Synthesis and properties of non-isocyanate polyurethane coatings derived from cyclic carbonate-functionalized polysiloxanes

To improve the chemical resistance of non-isocyanate polyurethane (NIPU), two kinds of diglycidyl ether, bisphenol AF (E-AF) and perfluorooctyl glycidyl ether (PFGE), were selected to synthesize two different cyclic carbonates, bisphenol AF (EC-AF) and perfluorooctyl cyclic carbonate (PFGC), respectively. These cyclic carbonates were successfully used to prepare fluorine-containing non-isocyanate polyurethane coatings. The effects of PFGC amounts on the properties of NIPU were studied, and it was found that the contact angles of water, diiodomethane, and hexadecane were increased with the addition of PFGC and up to 106.7°, 80.2°, and 72.7°, respectively, whereas the pendulum hardness of NIPU coatings relatively decreased with the increase in PFGC contents. The NIPU coatings exhibited excellent flexibility, adhesion, and impact resistance. They also displayed good thermal stability with 5% weight loss temperature (T5%) ranging from 249 to 271°C. Moreover, these coatings possessed very low water uptake, excellent hydrophobic/oleophobic properties, and corrosion resistance properties.

The utilization of renewable resources to provide a flame-retardant coating trend based on non-isocyanate polyurethane (NIPU) materials is inevitable. In this work, a series of advanced NIPU polymer was fabricated by the reaction of a cyclocarbonate and aromatic diamine. Sunflower oil cyclocarbonate was prepared by epoxidizing the oil using hydrogen peroxide in epoxidation reaction. The carbon dioxide was used for the cyclocarbonation process. The epoxidized product was subjected to a facile carbonized with carbon dioxide to yield ecofriendly cyclocarbonate. Zirconia @ silica (ZrO2@ SiO2) particles were formed by in situ method which binds zirconia nanoparticles with silica nanospheres. Aminolysis curing reaction was performed between the cyclocarbonate and 1,4-phenylendiamine to yield NIPU coating film for flame retardant applications. Various concentrations of ZrO2@SiO2 nanofillers were incorporated in NIPU matrix. Each product was analyzed and approved by using different investigation methods. The thermal stability and flammability properties were studied via thermal gravimetric analysis (TGA), limiting oxygen index (LOI). Mechanical performance and chemical resistance were evaluated as durability factors. High flammability resistance was shown where a high tolerance to direct fire contact was observed without ignition. Excellent mechanical properties and chemical stability for the prepared NIPU coatings were discussed in comparison by previous studies for NIPUs.

This work deals with the development of non-isocyanate polyurethane (NIPU) composites with an aniline oligomer, viz., tetraniline (TANI) for corrosion-resistant coatings. Firstly, epoxidizedsoyabean oil was converted to carbonated oil by inserting CO2 under high temperature and pressure into the epoxy ring. Then, varying weights of oligoaniline—0.5, 1, 2 and 4 wt % (based on the weight of CSBO)—were added to CSBO and cured with tetraethylenepentamine (TEPA, 25 wt % based on CSBO) at 80 °C for 12–15 h. The effects of oligomer loading on the thermal, mechanical and surface wetting properties of the free standing films were studied. The ATR-FTIR spectra of the films exhibited peaks corresponding to the bis-carbamate linkages, confirming the formation of urethane linkages. TGA analysis showed that the addition of oligoaniline did not alter the initial degradation temperature much; however, the residue increased with increasing loading of tetraniline. Both tensile strength and elongation (at break) increased with increasing oligoaniline content. While the glass transition temperature of the films was observed at approximately room temperature, i.e., 20–30 °C, for all the compositions, the contact angles of the composites were found to be less than that of the bare NIPU films. However, all the compositions were hydrophobic, exhibiting contact angles in the 98–110° range. SEM analysis of the cross-sections of the films confirmed the uniform distribution of tetraniline particles and surface morphology showed that the roughness increased with the loading of tetraniline from 0.5 to 4%. MS panels coated with NIPU exhibited good barrier properties and as loading of TANI increased, the rate of corrosion decreased. Salt spray tests indicated that oligoaniline improved the adhesion of the coating to MS and corrosion resistance compared to the neat NIPU coating.

Diradicals or Zwitterions: The Chemical States of <i>m</i> -Benzoquinone and Structural Variation after Storage of Li Ions

Non-isocyanate polyurethane (NIPU) from tris-2-hydroxy ethyl isocyanurate modified fatty acid for coating applications