• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.75-80
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• 1997

This research has been examined to measure the degree of the fiber damage of ozonenation high yield pulp in the beating process. Ozone treated the TMP(Thermomechanical Pulp) and CTMP(Chemithermomechanical Pulp) of spruce and the CTMP of birch has been beaten to be reached 200ml(freeness) of its content. It had been studied the forming of fiber distribution by treatment for long fiber, short fiber, fine with the above method. As ozone treatment time gets longer, the pulp has showed the tendency of increasing the fiber content of 28, 48mesh. Ozone treated fiber has been increased long fiber content by being added softness. By given longer ozone treatment time, the TMP and CTMP of spruce has showed the decreasing of fiber content. On the contrary, CTMP of birch has showed the increasing its fiber content. It had proved that the results of difference are rather closer to the species of tree than closer to the kinds of pulp. The fiber content of over 200mesh which has created in beating process demonstrates the decreasing of its fiber content by getting longer ozone treatment time. The softness of fiber can be extracted by the lignin of fiber surface that had been formed by ozone treatment. Thus we assume that the fiber in the process of beating obtains less physical damage.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.148-153
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• 2003

The influence of sizing, fiber and pigment type on coating penetration, using commercial paper and two types of handsheets as the base paper which were prepared from thermomechanical pulp(TMP) and hardwood bleached kraft pulp(KP) sized internally with alkyl ketone dimmer(AKD), was studied in terms of characteristics of coating holdout. Laboratory rod draw down coater was used for surface sizing and coating application. Characterization of coating penetration was done by measuring the roughness of the backside of coating layer. The backside of the coating was exposed by dissolving the fibers in a solution of cupriethylenedimine(CED). Data show that internal sizing of base paper is effective and surface sizing is more effective to prevent coating penetration. Comparing between the two types of base papers, backside roughness of coating layer of TMP sheet is much larger and sizing is more effective to reduce coating penetration than those of KP sheet. With regard to pigment type, clay is more effective than calcium carbonate for better coating holdout.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.1
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• pp.1-6
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• 2002

Alkaline sizing characteristics of TMP (thermomechanical pulp) handsheets with AKD (alkylketene dimer) were studied under various conditions. The sizing degree of TMP handsheet was much lower than that of chemical pulp. Especially, the sized TMP handsheet dried at $20^{\circ}C$ showed no sizing features, but sizing degree of TMP handsheet was clearly Increased by heat treatment at $105^{\circ}C$. The sizing effect of TMP was also improved by addition of $CaCO_3$, but it was not affected by pH. Therefore, sizing effect of TMP with AKD can be improved to some extent by controlling stock condition and heat treatment of handsheet.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.22-29
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• 2002

This research was conducted to investigate the morphological characteristics of fine fibers produced during beating process of high yield pulp treated with ozone and the distribution of lignin in the produced fine fibers. Thermomechanical(TMP) pulp and chemithermomechanical(CTMP) pulp of spruce and CTMP of white birch were beaten to reach 200$m\ell$ CSF, and then the fine fibers were observed using ultraviolet microscope. The fine fibers produced from TMP and CTMP of spruce using treated with ozone for 15 minutes were fragments of fiber surfaces or cell corners, and most of them contained lignin. However, lignin was not observed in the fibers after 15 minutes of ozone treatment. The fine fibers produced from CTMP of white birch were broken pieces or fragments of fiber surfaces or cell corners. The lignin was observed in the fibers until 5min of ozone treatment but no lignin was observed after 5 minutes of ozone treatment. Different morphological characteristics of TMP and CTMP explained both the different morphological characteristics and the distribution of lignin observed in the fine fibers produced from the beating process of TMP and CTMP treated with ozone.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.04a
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• pp.178-182
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• 2008

The bleached red algae fiber(BRAF) showed very similar crystallinity to the cellulose, furthermore, it has higher thermal decomposition temperature than that of the microcrystalline cellulose(MCC). Polypropylene biocomposites reinforced with BRAF have been fabricated with various BRAF contents by compression molding method and their mechanical and thermomechanical properties have been studied. The mechanical strength as tensile, impact and flexural modulus of BRAF/PP biocomposites were gradually improved with increasing the BRAF content, and thermal property which against the thermal expansion was markdly improved, especially. These results are compared with chopped non-woody fibers as Henequen or Kenaf, BRAF was more effective for fabrication of biocomposites reinforced small-sized fibers. The red algae fiber reinforced biocomposites has the applicability such as electronics, biodegradable products and small-structure composites.

• Journal of Biosystems Engineering
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• v.30 no.5 s.112
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• pp.285-292
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• 2005

Extrusion process and physical properties of extrudates of pulp powder (TMP, thermomechanical pulp fibers) mixed with expanding additives was evaluated to develop biodegradable packaging materials. To find out the optimum condition, the status of extrusion process, coefficient of elastic and expansion ratio of extrudates were tested on the composites (wheat flour, soluble starch, polyvinyl alcohol), blending conditions of composites and moisture contents of extrudates. In case of material composition, wheat flour played a key role to keep extrusion process irrespective of the added amounts of soluble starch and polyvinyl alcohol. The coefficient of elastic of extrudates was increased and the expansion ratio was reduced as the added amounts of wheat flour increased. Also, the coefficient of elastic of extrudates was decreased as the moisture content of extrudates increased. The lowest coefficient of elastic was 439.55 kPa under the condition, of pulp powder mixed with $20\%$ of wheat flour based on pulp weight and $10\%$ of soluble starch based on wheat flour weight and controlled $20\%$(wb) of moisture content.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.112-119
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• 2015

The pulp mold attract the increasing concern as recyclable, biodegradable, and eco-friendly packaging materials. In order to broaden the applicability of the pulp mold as substitutes of the expanded styrofoam, the properties of various raw materials for the pulp mold were evaluated and the way for improving water resistance properties of the pulp mold were also tested by applying some additives. The higher value in the fines contents and in the water retention value were shown for the TMP (thermomechanical pulp), which resulted in the bulkier pulp mold with the higher moisture absorption property. In case of water resistance properties, the pulp mold made of white ledger stock showed the higher value in water contact angle and very slow water absorption rate. The addition of oil palm EFB fiber showed the improvement in the water resistance of the pulp mold made of UBKP. The effects of various additives on the improvement in the water resistance properties of the pulp mold were tested by using AKD, PVAm, epoxy resin. The application of AKD leaded to the higher increase in the water resistance. The results in this study showed the effects of AKD for the pulp mold could be improved and optimized by the application with fixing agent and by the ageing treatment after production.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11a
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• pp.180-186
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• 1999

Alkaline peroxide bleaching of (chemi) mechanical pulp is a very complicated system where various process factors affect the bleaching performance and pulp properties. Traditional on-factor-at a time method is ineffective and costly in finding the optimal bleaching conditions. In this study statistical experimental methods which include three steps. I. e. screening, response surface modeling and optimization, were used to find the conditions for maximal brightness development during one stage alkaline peroxide bleaching of TMP which had an initial brightness of 54.5% Elerpho. The TMP was pretreated with EDTA(0.5% on O. D. pulp. consistency, $30^{\circ}C$ for 60 minutes) and bleached in a 2L Mark V Quantum Reactor at 750rpm, 7.5% of bleaching consistency and with 0.05% magnesium sulfate addition. The ranges of other factors studied were 1~5% hydrogen peroxide on O. D plup, 1~4% sodium hydroxide on O. D pulp and 1~4% sodium silicate on O. D pulp, reaction temperature 50~$90^{\circ}C$ and reaction time 40~180minutes. A models with good predictability was established and the maximal brightness after one stage bleaching was found to be 70% Elerpho at $50^{\circ}C$, 50 minutes 5% hydrogen peroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D pulp and 4% silicate on O. D pulp. However further studies on other pulp properties such as strength and brightness stability shall be carried out in order to find out the optimal bleaching conditions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.5
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• pp.1-7
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• 2000

Alkaline Sizing behavior and mechanism of handsheets, which were prepared from thermomechanical pulp (TMP) with alkylketene dimer (AKD), were studied in terms of the conditions of the handsheet-making. AKD content in the TMP handsheets was increased with increasing of AKD addition level and the addition of a polyamideamine-epichlorohydrin resin (PAE) clearly enhanced AKD retention as well as the resultant sizing performance of TMP handsheets. Although drying of the AKD sized TMP webs at $20^{\circ}C$ led to no or quite low sizing level, but TMP handsheets sized with AKD had higher sizing degrees with increasing of the temperature of heat treatment. Scanning electron microscopic observations of the AKD-sized TMP handsheets showed that AKD emulsion particles were present on pulp fiber surfaces independently without coagulation in the TMP handsheets dried at $20^{\circ}C$. Heat treatment of the AKD-sized handsheets resulted in disappearance of the AKD emulsion particles because of their melting and spreading. The addition of calcium carbonate filler to the TMP suspensions did not influence on AKD content in the TMP handsheets. Nevertheless, their sizing degrees clearly increased by the addition of $CaCO_3$filler. Probably, AKD molecules adsorbed on the $CaCO_3$filler particles contribute to the enhancement of sizing performance. Thus, AKD can give sizing features effectively to the TMP handsheets, when they are made under suitable conditions.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.475-478
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• 2006

Environment-friendly shock-absorbing materials were made using a vacuum forming method from waste wood collected from local mountains in Korea. The waste wood was pulped by thermomechanical pulping. The TMP cushions showed superior shock-absorbing properties with lower elastic moduli compared to EPS and pulp mold. Even though the TMP cushions made using different suction times had many free voids in their inner fiber structure, their apparent densities were a little higher than EPS and much lower than pulp mold. The addition of cationic starch improved the elastic modulus of the TMP cushions without increasing the apparent density, which was different from surface sizing with starch. The porosity of the TMP cushions was a little greater than EPS and much less than pulp mold. Finally, the TMP cushions have great potential to endure external impacts occurring during goods distribution.