• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2003.11a
• /
• pp.17-26
• /
• 2003

Nalita wood(Trema orientalis) is one of the fastest growing woods in the world. It may be a viable species for pulpwood. The physical, chemical and morphological properties of Nalita were studied. The total lignin, pentosan and holocellulose content in Nalita wood were 24.7%, 22% and 81.2%, respectively. Its fiber length was about 0.92 mm, which are comparable to Acacia mangium. Nitrobenzene oxidation of Nalita wood meal indicated that the guaciayl and syringyl unit were the major constituent of Nalita lignin. Nalita produced 50% pulp yield at Kappa number 21 in soda-anthraquinone process. The strength properties of Nalita pulp were comparable to other tropical hardwood pulp. At $40_{\circ}$ SR, the breaking length, burst index, tear index and total energy absorption were 6000 m, $3.5kPa{\cdot}m^2/g\;and\;7.0mN{\cdot}m^2/g\;and\;75J/m^2$, respectively.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.42 no.1
• /
• pp.48-53
• /
• 2010

Commercial micro pulps(Arbocel) were coated with three kinds of polymers using spray method. These coated micro pulps were used to papermaking additives to evaluate retention, drainage and physical properties of paper. The retention and drainage were improved with addition of polymer coated micro pulp. The bulk index of paper was also increased, but tensile and tear strength were decreased slightly, probably due to weakening of internal bonding. These results showed that the use of polymer coated micro pulp was an effective method to improve retention, drainage and bulk index of paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.30 no.2
• /
• pp.55-61
• /
• 1998

This treatment was applied to bleached softwood kraft pulp handsheets in an effort to improve physical strength of paper. Paper strength was improved by esterification of cellulose and polycarboxylic acid. Because hydrogen bond of carboxyl group is stronger than that of hydroxyl group, polycarboxylic acid forms stronger hydrogen bond than cellulose does. 1,2,3,4,-cyclopentanetetracarboxylic acid (CPTA) and sodium dihydrogen phosphate ($NaH_2O_4$) were used as polycarboxylic acid and catalyst, respectively This reaction was confirmed by the weight gain of the handsheets, by FTIR spectrum and by changes in mechanical properties of sheets. Wet tensile strength was improved when handsheets were treated with polycarboxylic acid. However, tear strength and burst strength decreased.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.3 s.174
• /
• pp.625-633
• /
• 2000

The mechanical and curing properties of short nylon66 fiber reinforced Chloroprene rubber have been investigated as functions of interphase conditions and fiber content. The tensile strength exhibits a dilution effect at a low fiber content in each interphase. It is found that the interphase conditions have an important affect on the dilution ratio and critical fiber content. Double coatings of bonding agent 402 and rubber solution become the best interphase model in this study. The yield strength, tensile modulus, tear strength and fracture toughness at rupture, Jr are significantly improved due to fiber concentration.

• Clinics in Shoulder and Elbow
• /
• v.20 no.2
• /
• pp.105-112
• /
• 2017

Rotator cuff tears commonly affect the shoulder joints. Despite developments in surgical techniques and instrumentation, the treatment of massive rotator cuff tears remains challenging. The problems associated with rotator cuff repairs, such as inferior mechanical properties and high retear rates are yet to be solved. Recently, patch augmentation has been suggested as an alternative treatment because it can reinforce mechanical properties at the initial stage of healing and reduce gap formation. The purpose of this article was to comprehensively summarize the concepts and the consensus surrounding patch augmentation and evaluate the clinical and anatomical outcomes after patch augmentation for massive rotator cuff tears.

• Archives of Plastic Surgery
• /
• v.35 no.6
• /
• pp.659-662
• /
• 2008

Purpose: Silicone gel sheet(SGS) is used for preventing and treating keloid or hypertrophic scars. Because the product is weak in tear strength and adherence, it requires several replacements, which requires high cost. As a solution for this problem, we developed a new silicone gel sheet, named as Scar Clinic, and confirmed its physical properties. Methods: Tensile strength, elongation rate, adhesiveness, and water vapor transmission rate were experimentally compared between the most commonly used SGS product and the Scar Clinic. Results: The newly developed SGS showed better results compared to the existed SGS in regards to tensile strength, elongation rate, adhesiveness, and water vapor transmission rate. Conclusion: The Scar Clinic showed higher durability and flexibility. It will be a useful product for treating scars clinically.

• Journal of the Korean Applied Science and Technology
• /
• v.12 no.2
• /
• pp.75-83
• /
• 1995

1, 3-Di(2-dodecanoylaminoethyl)-2, 7-dioxy-1, 3, 6, 8-tetraazacyclodecane[DDTD] and sorbitan monostearate(SMS) were synthesized as a main component for softner. O/W type softner(DSA) was prepared by blending of DSA, SMS, polyoxyethylene(10) castor oil, glyceryl monooleate, and polyoxyethylene(7) stearyl ether. After treatment of DSA to all cotton fabrics, the physical properties such as tear strength, crease recovery, and flexing abrasion resistance were measured. As a result of the measurement, DSA was found to be durable softner with good softness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.40 no.3
• /
• pp.30-35
• /
• 2008

Mechanical properties of paper mulberry bast fiber handsheets were investigated to study the characteristics of bast fiber in terms of being suitable for modern paper making process. Tensile, tear and burst strength of handsheets made from bast fiber of paper mulberry were better than those of NBKP handsheets. Smoothness of bast fiber was higher but stiffness was lower than NBKP. Sizing performance of bast fiber were worse. 3D image analysis showed that handsheets of bast fiber had inferior formation and more pores comparing to NBKP.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.35 no.4
• /
• pp.1-7
• /
• 2003

In this study, fiber mechanical pretreatment before refining was executed with the addition of papermaking addiditives to find synergistic effects on fiber property improvement. Three fiber furnishes (SwBKP, KOCC, and BCTMP), and five different additives (CMC, CPAM, PEO, NaOH, $Na_2O_2$) were used. It was confirmed again that fiber mechanical pretreatment using Hobart mixer was a special way to modify fiber properties, where fiber WRV (water retention value) increases without losing fiber length. For SwBKP, addition of small amount of CMC (0.2％ OD basis), and for KOCC, PEO (0.2％ OD basis) caused additional significant improvement of the fiber furnish properties, respectively. Other additives did not cause adverse effects on the mechanical pretreatment, or better. For BCTMP, NaOH addition followed by mechanical pretreatment caused more than 20％ improvement in tensile and tear strength simultaneously, compared to the control. The yellowing caused by the treatment of NaOH on BCTMP could be minimized by using $Na_2O_2$ without losing the positive effect of NaOH.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.35 no.4
• /
• pp.75-80
• /
• 2003

The purpose of this study was to design wedding dress by using Korean paper(Hanji). The Korean paper showed the good(excellent) properties of durability, softness, and tensile strength was 3.7Kg, tear index was 6 mN$.$$m_2$/g and folding numbers was 466. The appreance of Hanji was widely varied by blending(mixing) with other materials and various effects, pleating, crumpling, twisting and so on were achieved. The dress silhouette and form transformation of Hanji was very easy. Detailed points those are frill, pleats, gather, bow, paper casting, pin tuck for wedding dress were able to express easily. Hanji wedding dress has the natural texture because of natural properties of Hanji and that is echo friendly products.