• International Journal of Highway Engineering
• /
• v.16 no.6
• /
• pp.79-86
• /
• 2014

PURPOSES : In this study, wasted vinyl aggregate, which possesses better thermal properties than natural aggregate, was used in cement concrete mixture to develop more economical concrete with thermal insulation and freeze prevention effects. METHODS : Slump and air content of the fresh concrete, which substituted its 0%, 5%, and 10% of coarse aggregate with wasted vinyl aggregate, were measured. Compressive strength, Poisson's ratio, elastic modulus, and splitting tensile strength of hardened concrete were measured by laboratory tests. Thermal properties of concrete such as coefficient of thermal expansion, thermal conductivity, and specific heat were also measured according to replacement ratio of wasted vinyl aggregate. Finally, the thermal insulation and freeze prevention effectiveness of the concrete mixed with wasted vinyl aggregate was confirmed through finite element analysis of road pavement crossing above concrete box culvert made from wasted vinyl aggregate. RESULTS : Even though the physical properties of wasted-vinyl-aggregate concrete such as compressive strength, Poisson°Øs ratio, elastic modulus, and splitting tensile strength were inferior to those of ordinary concrete, they met requirements for structural concrete. The thermal properties of concrete were improved by wasted vinyl aggregate because it decreased thermal conductivity and increased specific heat of the concrete. According to the result of finite element analysis, temperature variation in pavement subgrade was mitigated by box culvert made from wasted-vinyl-aggregate concrete. CONCLUSIONS : Through the laboratory test and finite element analysis of this study, it was concluded that the concrete structures made from wasted vinyl aggregate showed thermal insulation and freeze prevention effects.

• Journal of Adhesion and Interface
• /
• v.11 no.3
• /
• pp.89-99
• /
• 2010

In this paper, for polymerization of poly(vinyl acetate-co-ethylene) (VAE) by redox system using poly(vinyl alcohol) (PVOH) as emulsifier on the properties of the final emulsion, and pH changes affect the physical properties of the final emulsion was investigated. The results of the molecular weight of PVOH had a dramatic impact on the emulsion properties. The used a low molecular weight of PVOH products was obtained low viscosity and using the high molecular weight of PVOH were obtained high viscosity product. However, changing the pH of the final polymerized product properties for the PVOH obtained different results. Generally, a poly(vinyl acetate) emulsion by a high degree of polymerization and high molecular weight of PVOH was obtained high viscosity of the final emulsion. But, in VAE was lower emulsion viscosity in high pH. This is the molecular weight of the emulsion during the synthesis of PVOH is considered to be affected by degradation. The final viscosity was decreased by grafting ratio and molecular weight were decreased with increasing of pH.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.8 no.1
• /
• pp.37-42
• /
• 2009

This paper describes the fuel oil characteristics of mulching waste vinyl by indirect heating emulsion system. For the emulsion experiment of waste vinyl, the system is composed of melting furnace, the 1th pyrolysis furnace, and the 2nd pyrolysis furnace. The mulching waste vinyl is used for the fuel oil characteristics analysis of mulching waste vinyl. The refined oil, gasoline, and diesel oil are extracted and quantified to analysis the fuel oil characteristics. From the results of experiments, it has been shown that the production of fuel oil from mulching waste vinyl is possible using the emulsion system.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.57 no.5
• /
• pp.13-17
• /
• 2015

There are many vinyl houses in rural areas. These vinyl houses have occasionally been collapsed due to heavy snow load in winter. If these vinyl houses are collapsed, many farmers get a lot of economical damages. So it is very important to built safe vinyl house that is able to withstand the applied heavy snow load. In this study, compressive buckling and flexural tests were performed to investigate the strength increase of circular mortar filled pipes. The results showed that buckling load and flexural moment of mortar filled pipes were increased 42 % ~ 82 %, 40 % ~ 44 % respectively more than only pipe without mortar. It is recommended that mortar filled pipes as main members of vinyl house have to be used to prevent collapsing due to the severe snow load.

• Proceedings of the Korean Fiber Society Conference
• /
• 2003.10b
• /
• pp.46-48
• /
• 2003

Poly(vinyl alcohol) (PVA) obtained from PVPi has the highest syndiotacticity among (PVA)s obtained via radical polymerization, and the s-diad content of PVA prepared by low temperature polymerization of vinyl pivalate (VPi)[1-5] comes to eve. 60%, Therefore, we an obtain (PVA)s with various tacticities through the copolymerization of vinyl acetate (VAc) and VPi and can examine the relation between physical properties of (PVA)s and their tacticities. (omitted)

• Journal of the Korean Applied Science and Technology
• /
• v.6 no.1
• /
• pp.21-26
• /
• 1989

Four fatty acid vinyl esters were synthesized by transesterification between vinyl acetate and lauric acid, myristic acid, palmitic acid, stearic acid, respectively. Fatty acid vinyl ester oligomers were prepared from polymerization of four fatty acid vinyl esters in the presence of potassium persulfate in methanol. The ${\alpha}-sulfonation$ of these four fatty acid vinyl ester oligomer were carried by direct addition of sulfur trioxide. Especially, molecular weights of sodium ${\alpha}-sulfo$ fatty acid vinyl ester oligomers were measured by boiling point method.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.33 no.5
• /
• pp.437-444
• /
• 2007

Vinyl acetate has been widely used for the manufacture of polyvinyl alcohol emulsion, which is primary ingredient of adhesive, paints, textile, paperboard coatings, etc. Since these products are plentiful and frequently used around us, workers and consumers are at health risk. International Agency for Research on Cancer(IARC) classified vinyl acetate as group 2B(possibly carcinogenic to humans). Among the organs targeted, the oral cavity is the most vulnerable organ affected by the carcinogenic effects of vinyl acetate. Since the origin of most of oral cancer is derived from the epithelial cells, it is important to understand the carcinogenic potential of vinyl acetate in human epithelial cells. Thus, the present study has attempted to utilize the immortalized human epithelial cell model to assess the carcinogenic potency of this chemical and to understand the underlying mechanisms.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.69-70
• /
• 2006

Waste vinyl tretreatment system has been developed by the joint project between KIMM and Woosung Co. General process for removal of impurities from waste vinyl is consisted of feeding, separating, cutting, washing, drying and recovering impurities. However, there are problems such as wastewater when washing of waste vinyl. In order to solve these problems we have developed new dry type cleaning system.

• Journal of the Korean Society of Tobacco Science
• /
• v.8 no.2
• /
• pp.43-49
• /
• 1986

Field experiment was conducted to investigate the effect of vinyl mulch on phosphate availability of soil and fertilizer in 1982. Growth of tobacco was more vigorous at each level of phosphate treatment in vinyl mulched than in bare soil. There was significant culture x Phosphorus treatment interaction for the yields of cured tobacco leaves. These results indicated that vinyl mulch was effective to improve phosphate availability of soil and fertilizer. Increase in soil temperature and maintenance of bulk density suitable for Phosphorus diffusion by vinyl mulch were likely to Play major roles on Phosphate availability, but other unknown factors appeared to be involved.

• Proceedings of the Korean Fiber Society Conference
• /
• 2001.10a
• /
• pp.187-190
• /
• 2001

The poly(vinyl alcohol) (PVA) fiber is recognized as the best candidate because of its good machanical properties together with excellent resistance to alkalis[1-5]. PVA cannot be prepared by the direct polymerization due to tautomerism of vinyl alcohol monomer. Thus PVA is obtained by the saponification of poly(vinyl ester) like poly(vinyl acetate) (PVAc). (omitted)