• Journal of the Korean Applied Science and Technology
• /
• v.26 no.2
• /
• pp.213-223
• /
• 2009

Conventional additives were added to a newly synthesized base oil to create synthetic lubricants. Commercial polyol ester prepared in this laboratory were obtained as esterification of 1,1,1-trimethylol propane and respectively. This newly synthesized base oil had a variable chemical structure that could achieved the following properties; oxidation or thermal stability, low temperature fluidity, and higher flash points. When compared with commercial mineral lubricants, the synthetic lubricants show superior thermal and oxidation stability, and anti-wear properties.

• Journal of the Korean Applied Science and Technology
• /
• v.27 no.4
• /
• pp.522-530
• /
• 2010

We developed functional synthetic lubricant for internal combustion engine oil, which would improve engine oil performance for internal combustion engine and extend engine life. We made base oil by synthesizing nonanoic acid, 1.1.1-trimethylol propane (which has good bio-degradability) and pentaerythrytol ester. We synthesized catalyst using p-toluene sulfonic acid 0.15 wt% and coloring-prevention agent hypo-phosphorus acid 0.18 wt% at 180-$190^{\circ}C$. Reaction temperature was increased at the rate of $10^{\circ}C$ for every 1 hour. When acid value reached below 3, reaction was completed. After cooling and deoxidization, we washed it by distilled water two times. After dehydration and filtering, we obtained trimethylol propane tripelargonate (TMTP) and pentaerythrytol tetrapelargonate (PETP) at yields of 96 % and 98 % respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.14 no.1
• /
• pp.35-42
• /
• 2008

Twenty eight gas impermeable plastic films for food-contact application were collected in the domestic market and material and/or migration tests for overall migration, antioxidants, potassium permanganate consumption, heavy metal, and plasticizers were carried out. The average overall migration values for NY/PE or NY/LLDPE, PETP/PE, and PVDC packaging films obtained by using n-heptane as fatty food simulant were 7.6, 6.9 and 14.1 mg/L, respectively. These values were much lower than the limit values of 150 and 30 mg/L for polyethylene and polyvinylidene chloride prescribed in the Korea Food Code. In almost of the packaging materials tested, the antioxidants such as Irganox 1010, Irganox 1076 and Irgafos 168 were found. The migration test result showed that almost of all samples except PVDC film contained Irganox 1076 and Irgafos 168, while the maximum migration value of Irganox 1076 into n-heptane was found in the Ny/PE/LLDPE(15/25/50 ${\mu}m$) sample at the concentration of 216.9 ${\mu}g/g$. From the plastic packaging samples tested, plasticizers such as DEP, DPRP, DBP, DPP, BBP, DCHP, DEHP, DEHA and observed above the detection limit. Consumption amount of potassium permanganate was much lower than the limit value of 10 mg/L. In the material test for heavy metals, cadmium and lead were determined at the concentrations far below the limit value of 100 mg/kg. The migration test for cadmium and lead showed a lower value than the detection limit. Therefore, it can be concluded that the safety status of the plastic films tested met the requirement of limit values as prescribed for the material and migration tests of food packaging utensils, containers and packages of the Korea Food Code.

• Food Science of Animal Resources
• /
• v.30 no.4
• /
• pp.674-684
• /
• 2010

The effects of ascorbic acid (AA) alone or in combination with sodium acetate/calcium lactate (AA+SACL) and chitosan (AA+CH) on the physicochemical properties and microbial growth of beef and pork patties stored at $5^{\circ}C$ were investigated. The patties were case-ready packed in an air-containing polypropylene (PP) tray and sealed with polyethylene terephthlate (PETP)/casted polypropylene (CPP) top film. Treatments with AA, AA+SACL and AA+CH were effective in inhibiting total aerobic bacteria from day 4 compared to the control. In general, thiobarbituric acid, volatile basic nitrogen, and hue values in treated samples were lower than the control over the storage, whereas Hunter ${\alpha}^*$ (redness) values and sensory scores for surface color and off-odor were higher. Regarding quality and shelf-life extension, ground beef and pork patties treated with AA+SACL produced the most desirable results among all treatments during storage.