4HBA 변성 High Solid 아크릴 우레탄도료의 반응성·물성 및 부식평가에 관한 연구

Abstract

2 components polyurethane coating is generally often used for the industry due to its excellent performance and workability by 3 dimensional cross linked chain structure that is built from the reaction between polyol and polyisocyanate.Viscoelasticity is measured by rheometer, DMA and RPT-3000. Reactivity using absorption peak is measured by FTIR. As a result of this test, reactivity of polyol and polyisocyanate is affected by catalyst, OH values and chemical composition. In result, polyester is the fastest and alkyd is the slowest. Acrylic polyol and polyester modified acrylic polyol reacted differently by the temperature and catalyst. And the more OH values are high, the more reaction rate is fast. Thus depending on what kind of reactivity and film performance are selected, many problems that are difficult to apply on work site can be resolved and improved.12 kinds of mixtures made from 6 kinds of polyols and hardeners are measured for dynamic viscoelasticity by DMA and Rheometer instrument. The test showed that each polyol has different mechanical and chemical properties. And this result can be practicable for resolving the painting problems and developing the paint technique.As a result of this test, mechanical property of No.2 alkyd polyol and No. 6 acrylic polyol with reaction of aliphatic polyisocyanate Desmodure N3300 is the most excellent. The high molecular weight of alkyd polyol and high Tg and low OH values of acrylic polyol has excellent mechanical property. In case of polyester, it has good property (reactivity, mechanical property, adhesion and anti-corrosion) with aliphatic hardener as a primer binder but it is defective as 2 components painting system due to its short pot life.No. 9 alkyd polyol with the aromatic hardener Desmodure L75 has better adhesion and anti-corrosion than acrylic polyol but dry time is a little slow to be used for 2 components painting system. And alkali resistance (5% NaOH) is good but a little less than acrylic polyol. No.6 Acrylic polyol paint reacted with Aliphatic hardener "Desmodur N3300" has a good result of a mechanical property, hardness, weather ability and heat-resisting property in order to endure in exterior, therefore, Desmodur N3300 is decided as a optical binder. I can cook 70% high solid resin measured 3 poly dispersity Index A 98% conversion that is applied as 5~7% TAPEA initiator, 1~3% of methyl styrene chain transfer agent and various monomers. After that, it is composed to high solid Tone M100, 4HBA and 2HEMA monomer modified acrylic polyol resin for paints with 10~20 Poise of Viscosity (25℃, Gardener U~Y). However, a property of film is going to be deteriorated due to low molecular weight of resin. According to a this result, for making reaction speed up, when Tone M100, 4HBA, 2HEMA etc, which can be a bigger molecular weight in bridge-building, are modified, then the urethane bonding reaction is measured by rheometer for Pot life(Gel time) with the store modulus of elasticity G' and loss modulus of elasticity G". According to a measured result of Tg of the film by activation Energy in ARRENIUS formula and dynamic viscoelastic with DMA. The reactivity rate of 4HBA modified high solid acrylic polyol with others as well as has low activation energy among K-KAT 4205, K-KAT 348 and DBTDL used now. The K-KAT 4205 and K-KAT 348 are shown the high activation energy than DBTDL. Anti-rust primer coating with poly isocyanate N3600 hardener is built by selected three type of resin "Modified high solid 4HBA, Tone M100 modified high solid acrylic polyol resin and general used acrylic polyol resin" after additing two pigments " low toxicity anti-rust pigment 'Zinc Molybrate' so as to product metal by passivation and make it better workability, another is mica BaSO4 for malting film hard". Through the Test of NORSOK M501 and Thermal cycling test, we can find paint film how aging and Anti-corrosion performance by EIS (Electrochemical Impedance Spectroscopy) in measuring difference of the color, gloss, observing a surface of film and variation of an adhesion. A long period of time, HBA modified acrylic polyol resin coating is a little bit worse than high polymer type but a bit better than Tone M100 modified high solid acrylic polyol resin on a property of matter. In case of anti-rust pigment test, it has a very similar property between the low toxicity anti-rust pigment 'Zinc Molybrate' and a pigment 'Zinc Chromate'. As a result of this study, we were able to get the basic data which are necessary for applying 2 components high solid polyurethane paint and also reached a conclusion that it can be applied for developing new paints in terms of high performance, workability and environmental care.