• Journal of the Korean Applied Science and Technology
• /
• v.28 no.2
• /
• pp.203-212
• /
• 2011

In this study we experimented that how chain extension influences to waterborne urethane-acrylic hybrid resin for leather garment coatings. We knew that polyurethane-acrylic hybrid resins had 5 grades of solvent resistance. Tensile strength measured in the polyurethane-acrylic resin(EDA 5.37 g, 1.928 kgf/$mm^2$) had the most strong strength. Also polyurethane-acylic hybrid resin(EDA 5.37 g. 30.2 mg. loss) had better result than other hybrid resins. EDA contents higher, we obtained low elongation and low flexibility. In this result, chain extension of waterborne polyurethane-acrylic hybrid resin showed the effect in leather coating with ratio of EDA.

• Corrosion Science and Technology
• /
• v.5 no.2
• /
• pp.62-68
• /
• 2006

Solvent free high solid coatings are increasingly used as they posses number of advantages such as, lower cost per unit film thickness, better performance and eco-friendliness. In the present study polymeric film-forming materials such as aniline-novolac (ANS), cresol-novolac (CNS) and acrylic copolymer blended cresol-novolac (ACNS) coating materials have been prepared. The corrosion resistance properties of the prepared high solid coating materials have been evaluated through potential-time, potentiodynamic polarization and electrochemical impedance studies (EIS). Among the three coating systems, cresol-novolac polymer coated substrates offer better corrosion resistance property and the order of the performance was found as CNS > ACNS > ANS. We can recommend these systems for use in automobile applications.

• 보존과학연구
• /
• s.29
• /
• pp.183-197
• /
• 2008

Paraloid B-72 of acrylic resins has been widely used as consolidant for bronze artifacts conservation. In previous study, xylene was appropriate for paraloid B-72 when bronze artifacts consolidated. In this study, we compared the coating properties of paraloid B-72 in various concentration levels. The surface before and after coating were observed by optical microscope and AFM. Thickness and adhesive strength of films were tested. For testing coating stability, we performed yellowing test and EIS. After these experiments, we concluded 15wt% paraloid B-72 was adequate concentration for bronze artifacts conservation when paraloid B-72 used in xylene as solvent. Because 15wt% paraloid B-72 has the lowest polarity and high hydrophobic.

• Journal of the Korean Wood Science and Technology
• /
• v.25 no.3
• /
• pp.75-82
• /
• 1997

To improve the quality of coated paper, the continuous research to the coating components and development of alternative latices is required. Recently, amphoteric latex is getting a great concern due to their changable properties of surface charge through controlling pH and some methods have been tried to prepare amphoteric latices. This study was carried out to synthesize amphoteric latex using seeding polymerization method with low concentration emulsifier. Styrene was used as a main monomer in addition to acrylonitrile for a hydrophilic comonomer. acrylic acid for a anionic comonomer and N,N-dimethylaminoethyl methacrylate for a cationic comonomer. Particle size and viscosity of latex were greatly affected by addition of acrylic acid and ammonium persulfate as an initiator. Negative charge of latex in alkali condition was changed to zero to positive charge in around pH 4.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2011.04a
• /
• pp.327-338
• /
• 2011

This study was carried in order to manufacture the high quality coated paper. High quality includes not only properties of coated paper but also final print quality. In this study, new acrylic-styrene emulsion was polymerized in laboratory and compared with styrene-butadiene latex. Low-shear viscosity of coating color was decreased with increasing acrylic-emulsion dosage. WRV was increased with addition and decreased with substitution of acrylic-emulsion. Paper gloss, brightness and whiteness were increased and PPS and opacity was slightly decreased with acrylic-emulsion. Ink gloss was increased with using No. 3 acrylic-emulsion due to lower ink setting properties. However No.1, 2 emulsion shows opposite situation. Surface strength of coated paper was increased with using No. 3 acrylic-emulsion These results indicate that high quality coated paper can be manufactured with using No. 3 acrylic-emulsion.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.44 no.1
• /
• pp.37-42
• /
• 2012

This study was carried in order to manufacture the high quality coated paper. High quality includes not only physical and optical properties of coated paper but also final print quality. In this study, new acrylic-styrene emulsion was polymerized in laboratory and compared with conventional styrene-butadiene latex. Low-shear viscosity of coating color was decreased with increasing acrylic-emulsion dosage. Small amount of acrylic emulsion addition increased water retention, but further addition decreased it. Acrylic-emulsion addition improved paper gloss, brightness and whiteness, but decreased PPS and opacity slightly. Ink gloss was increased with using No. 3 acrylic-emulsion due to lower ink setting properties. However No. 1 and 2 emulsion showed the opposite result. Surface strength of coated paper was increased with using No. 3 acrylic-emulsion. These results indicate that high quality coated paper can be manufactured with using No. 3 acrylic-emulsion.

• Polymer(Korea)
• /
• v.24 no.4
• /
• pp.520-528
• /
• 2000

New high solid acrylic resins (BMHA) containing 70% of solids content have been synthesized. The environmental friendly high solid coatings (BNHS) were prepared by using these acrylic resins and polyisocyanates. The BMHA was obtained by introducing a new functional group, acetoacetoxyethyl methacrylate (AAEM), in the copolymerization of n-butyl acrylate, methyl methacrylate, and 2-hydroxyethyl acrylate. Lowering T$_{g}$ and increasing the AAEM amount in the BMHA resulted in a high value of conversion. There was no difference in conversion with the variations of OH values. In the next step, high solid BNHS coatings were prepared by the curing reaction between BMHA and polyisocyanate at room temperature. The properties of these coatings were evaluated especially for the application of automotive top-coating materials. The introduction of AAEM in the BNHS enhanced the abrasion resistance and solvent resistance of the coatings, which indicated the possible use of BNHS coatings for top-coating materials of automobile..

• Advances in materials Research
• /
• v.9 no.3
• /
• pp.219-231
• /
• 2020

The aim of this study is to investigate the durability of fly ash based geopolymer mortar with and without protective coatings in aggressive chemical environments. The source materials for geopolymer are Fly ash and Ground Granulated Blast furnace Slag (GGBS) and they are considered in the combination of 80% & 20% respectively. Two Molarities of NaOH solution were considered such as 8M and 10M. The ratio of binder to sand and Sodium silicate to Sodium hydroxide solution (Na₂SiO₃/NaOH) are taken as 1:2 and 2 respectively. The alkaline liquid to binder ratio is 0.4. Compressive strength tests were conducted at various ages of the mortar specimens. In order to evaluate the performance of coatings on geopolymer mortar under aggressive chemical environment, the mortar specimens were coated with two different types of coatings such as epoxy and Acrylic. They were then subjected to different chemical environments by immersing them in 10% standard solutions of each ammonium nitrate, sodium chloride and sulphuric acid. Drop in compressive strength as a result of chemical exposure was considered as a measure of chemical attack and the drop in compressive strength was measured after 30 and 60 days of chemical exposure. The compressive strength results following chemical exposure indicated that the specimens containing the acrylic coating proved to be more resistant to chemical attacks. The control specimen without coating showed a much greater degree of deterioration. Therefore, the application of acrylic coating was invariably much more effective in improving the compressive strength as well as the resistance of mortar against chemical attacks. The results also indicated that among all the aggressive attacks, the sulphate environment has the most adverse effect in terms of lowering the strength.

• Journal of Radiation Industry
• /
• v.5 no.4
• /
• pp.371-376
• /
• 2011

The surface property of the materials used in tissue engineering application has been essential to regulate cellular behaviors by directing their adhesion on the materials. To modulate surface property of the synthetic biodegradable materials, a variety of surface modification techniques have used to introduced surface functional groups or bioactive molecules, recently polydopamine coating method have been introduce as a facile modification method which can be coated on various materials such as polymers, metals, and ceramics regardless of their surface property. However, there are no reports about the degree of polydopamine coating on the materials with different hydrophilicity. In the present study, we prepared acrylic acid grafted nanofibrous meshes using electron-beam irradiation, and then coated meshes with polydopamine. Polydopamine successfully coated on the all meshes, both properties of acrylic acid and polydopamine were detected on the meshes. In addition, the degree of polydopamine deposition on the materials has been altered according to surface hydrophilicity, which was approximately 8-times greater than those on the non-modified materials. In conclusion, dual effect from the acrylic acid grafting and polydopamine may give a chance as a alternative tool in tissue engineering application.

• Journal of Conservation Science
• /
• v.27 no.4
• /
• pp.415-420
• /
• 2011

Urethane coating agent was made up in order to prevent corrosion on metal relics. This urethane coating agent was designed to solve problems linked to gloss and discoloration caused by existing acrylic coating agent which is mainly applied to metal relics. For the purpose, the urethane coating agent was made up which has lower gloss and slight color change. This coating agent formed thinner coating layer with excellent adhesion compared to the existing agent and has outstanding resistance to the surface oxidization of metal relics and water repellent on the surface. In addition, the agent is considered a stable coating agent replacing current acrylic coating agent with showing easy dissolution in organic solvents such as acetone, toluene and xylene with excellent result in reversible reaction.