• 한국산림과학회지
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• 제22권1호
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• pp.1-6
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• 1974

본(本) 연구(硏究)는 합판(合板)의 부후(부후)하는 성질(性質)를 개선(改善)하기 위하여 방부처리(防腐處理)를 실시(實施)하였을 때 그 접착강도(接着强度)와 방부력(防腐力)에 미치는 영향을 알아내기 위하여 실시(實施)하였다. 그 실험결과(實驗結果)를 종합(綜合)하면 다음과 같다. 1. 합판(合板)을 제작(製作)하여 그 합판(合板)을 직접(直接) 방부처리(防腐處理)하였을 때나 또는 단판(單板)을 미리 방부처리(防腐處理)하여 합판(合板)을 제작(製作)하였을 때나 모두 합판(合板)의 접착강도(接着强度)는 감소(減少)하지 않았다. 2. 합판(合板)을 마레니트(Malenit)로 처리(處理)하였을 때의 내부효력(耐腐効力)은 명확(明確)히 나타났으며 방부처리(防腐處理)를 하지 않은 합판(合板)이나 소나무 변재부(邊材部)와 비교(比較)하였을때 내부효력(耐腐効力)이 큰것으로 나타났다. 3. 방부효력(防腐効力) 실험결과(實驗結果) 동일(同一) 공시재(供試材)라 하여도 접종(接種)한 균종(菌腫)에 따라 중량감소(重量減少)에 차이(差異)가 있었으며 반대(反對)로 동일균(同一菌)을 접종(接種)하였을 때라도 공시재(供試材)의 종류(種類)에 따라 균(菌)의 호혐(好嫌)에 차이(差異)가 나타났다.

• 한국산림과학회지
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• 제60권1호
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• pp.37-44
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• 1983

요소수지(尿素樹脂)의 변성제(變性劑)로서 열가망성(熱可望性)의 아세톤수지(樹脂)를 첨가(添加)하고 합판(合板)의 접착력(接着力) 및 목파율(木破率)에 미치는 영향(影響)을 조사(調査)하였다. 결론(結論)을 요약(要約)하면 다음과 같다. 1) 합판(合板)의 접착력(接着力)과 목파율(木破率)은 열판온도(熱板溫度) $120^{\circ}C$에서 제조한 것이 가장 좋은 값을 보였으나 아세톤수지(樹脂)의 혼합비율(混合比率)이 증가(增加)함에 따라서 그 값은 점차 감소(減少)되었다. 2) 아세톤수지(樹脂)의 몰비율(比率)은 합판(合板)의 접착력(接着力) 및 목파율(木破率)에 영향(影響)을 미치지 않았다. 3) 아세톤수지(樹脂)를 혼용(混用)한 합판(合板)은 요소수지(尿素樹脂)만으로 접착(接着)된 합판(合板)의 접착력(接着力) 및 목파율(木破率)을 능가하지 못했다. 따라서 아세톤수지(樹脂)는 요소수지(尿素樹脂)의 변성제(變性劑)는 부적당(不適當)하였다.

• Journal of the Korean Wood Science and Technology
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• 제18권2호
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• pp.67-78
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• 1990

This study was performed to determine the characteristics of physical and mechanical properties of domestic wood based materials; plywood, particleboard, medium density fiberboard. Main items of tested properties were panel size, moisture content, water absorption, linear expansion and thickness swelling, glue bond shear strength, bending properties(stress at proportional limit, modulus of rupture. modulus of elasticity), tensile strength, screw holding strength, and internal bond as neccessary. the results were discussed mainly with Korean Standards. The obtained conclusions are as follows; 1. Length and width of 3mm thin plywood(3-ply) and 12mm thick plywood(7-ply) were satished with KS-standard, but thicknesses of these panels were not- passed tolerance limit except one of eight makers. 2. Length and width of particleboard and medium density fiberboard were greater than the tolerance limit value of KS standard, but the thicknesses of these panels were passed this value. 3. Moisture contents of 12mm thick and 3mm thin plywood were satisfied with KS-standard except one mill made 3mm thin plywood. 4. Moisture absortion of plywood was not passed tolerance limit of KS-standard but particleboard was satisfied with this standard value. 5. Dry and wet shear strengths in glue bond of 3mm thin plywood were not reached to KS-standard, but those of 12mm thick plywood were sufficiently satisfied with KS standrad. 6. Modulus of ruptures, parallel to grain and perpendicular to grain of plywood, and particleboard and medium density fiberboard were satisfied with KS-standard. 7. Tensile strengths, parallel to grain and perpendicular to grain of plywood were satisfied with allowance stress of US product standard PS 1-74. 8. Screw holding strength of particleboard was not reached to KS standard, but internal bond was satisfied with KS standard.

• Journal of the Korean Wood Science and Technology
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• 제12권1호
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• pp.38-43
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• 1984

Water soluble urea-melamine-phenol copolymer adhesive manufactured with 80 percent of urea resin contents was manufactured by different molar ratio for a high temperature curing type, and their properties and strengthes were examined through manufactures of plywood with Kapur (Dryobalanops spp.) veneers. The results are summarized as follows: 1. Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.78 to 0.84 and their moisture contents met the KS requirement. 2. In dry and wet shear strength, $U_{80}M_{10}P_{10}$ copolymer resin showed the highest value and urea resin was the lowest, indicating that melamine and phenol were effective for increasing glue shear strength of urea resin. 3. In case of glue shear strength after boiling test, phenolic resin was the nest and melamine was not so effective as phenol on reinforcement of boiling water resistance of urea resin.

• Journal of the Korean Wood Science and Technology
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• 제48권6호
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• pp.791-806
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• 2020

본 연구에서는 공학목재로 목구조건축에 주로 사용되는 집성재 및 CLT 그리고 Ply-lam CLT의 블록전단시험을 실시하여 강도 및 파괴 유형을 비교 분석하였다. 이를 통해 Ply-lam CLT의 라미나 및 합판의 수종, 접착제의 종류 및 Layer구성 등 최적생산을 위한 제조조건을 구명하고자 하였으며 그 결과는 다음과 같다. 블록전단시험을 통해 집성재, Ply-lam CLT, CLT 순으로 높은 강도를 나타냈다. 특히, 낙엽송 합판과 낙엽송 라미나의 복합구조로 제조되는 Ply-lam CLT의 전단강도는 집성재 전단강도 기준인 7.1 N/㎟을 통과하였다. 아울러 본 연구에서는 집성재, CLT, Ply-lam 접착에 사용된 접착제 종류에 따른 전단강도의 차이는 나타나지 않았다. 그러나 Ply-lam CLT의 경우에는 라미나와 합판의 수종에 따라 Ply-lam CLT의 전단강도의 차이를 나타냈다. 그 결과는 낙엽송 > 남양재 ≒ 육송 합판 순으로 높은 강도를 나타났다. Ply-lam CLT의 최적 구성은 낙엽송 합판과 낙엽송 라미나를 사용하는 경우이며 접착제는 용도에 따라 PRF, PUR을 선정하여 사용하면 될 것으로 판단된다. 목질재료 유형에 따른 전단강도 파괴 양상 결과 분석을 통하여 집성재는 shear parallel-to-grain, CLT는 rolling shear, Ply-lam CLT는 shear parallel-to-grain과 rolling shear가 복합적으로 나타났다. 이는 전단강도 결과와 밀접한 관련이 있으며 rolling shear로 인하여 CLT보다 Ply-lam CLT에서 더 높은 전단 강도를 나타내는 것으로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제24권2호
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• pp.42-45
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• 1996

A residue from the newsprint waste was investigated as a filler in adhesive for bonding southern pine plywood. The residue was prepared by drying the wet residue to 8% moisture content and grinding the dry material using a laboratory Wiley mitt with a 75-${\mu}m$(200-mesh) screen. The residue was compared to a commercial filler commonly used in structural plywood adhesives. A total of 48 three-ply panels. 12.7mm nominal thickness and 0.3 by 0.3 m in size, were fabricated at two press times(4 and 5 min) and three assembly times(20, 40 and 60 min). Evaluations of the residue were carried out by performance tension shear tests after two 4-hour boil accelerated aging tests on plywood. The test results included tension shear strength and estimated wood failure values. All plywood made with the residue filler were comparable to the control-bonded plywood. These results indicate that residue from the newsprint waste streams would be suitable as filler for plywood adhesives.

• Journal of the Korean Wood Science and Technology
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• 제38권5호
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• pp.414-420
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• 2010

The effect of polymeric diphenyl methane-4,4-diisocyanate (pMDI) or 1,6-hexamethylene diisocyanate (HDI) in the UMF resin was discussed for improvement of the dry and wet shear strengths of plywood manufactured from high moisture content veneers. The curing behavior of UMF resin by pMDI or HDI content was examined by DSC and TGA, and its adhesion performance was evaluated by dry and wet shear strength tests of plywood. With the increase of pMDI content in the UMF resin, the curing temperature, reaction enthalpy (${\Delta}H$), and thermal stability consistently increased. With the increase of HDI content in the UMF resin, however, the curing temperature and reaction enthalpy (${\Delta}H$) decreased consistently and the thermal stability slightly increased in the range of 200 to $400^{\circ}C$ but decreased beyond $400^{\circ}C$. Also, the dry tensile shear strength increased up to the pMDI content of 5% and then decreased with its further addition but the wet tensile shear strength showed slight tendency to increase with the increase of pMDI content in the UMF resin. As the HDI content increased, however, the dry and wet tensile shear strengths of plywood consistently increased.

• Journal of the Korean Wood Science and Technology
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• 제8권2호
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• pp.1-5
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• 1980

This study is carried out to determine the scavenging effect of resorcinol added into the urea formaldehyde resin on the formaldehyde release of plywood, as the preliminary study of using the phenolic substances. The method for formaldehyde determination used in this report is the improved chromotropic acid determination. The results are summarized as follows: 1. Resorcinol added into the urea formaldehyde adhesive acts as a good scavenger. 4 percent of resorcinol reduced the formaldehyde release to less than half content. 2. Adding resorcinol gave better glue shear strength than that of control, showing the peak of the shear strength, at 2 percent and decreased to the same strength as control along its content of 4 percent. 3. Moisture content of air dried plywood met the standard very well.

• Journal of the Korean Wood Science and Technology
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• 제1권2호
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• pp.11-15
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• 1973

This study was carried out to utilize sweet potato, and jerusalem artichoke flour as an extender of urea formaldehyde resin for plywood manufacture. The results obtained are summarized as follows: 1) In dry and wet test of plywood, sweet potato flour extended in urea formaldehyde resin was shown better strength than those of wheat flour. 2) Sweet potato flour was shown good results up to 200 percent extension in the dry test, and there was not shown significant difference between 100 percent and 150 percent extension in the wet test. 3) In the case of 100 percent extension, potato flour was shown best dry shear strength(400 psi) and sweet potato flour was shown best wet shear strength (212 psi).

• Journal of the Korean Wood Science and Technology
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• 제26권1호
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• pp.14-18
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• 1998

A low density polyethylene(LDPE) was examined as an additive in phenol-formaldehyde(PF) resin adhesive for bonding radiata pine plywood. The LDPE was supplied by the commercial manufacturer. The LDPE was compared to a commercial filler commonly used in structural plywood adhesives in the United States. The adhesive mixes were made by following the recommended procedure of Georgia-Pacific Resins Inc.. using plywood-type PF resin. A total of 48 three-ply plywoods. 6.3 mm nominal thickness and 30 by 30 em in size, were made at two press times (4 and 5 min). two press temperatures (150 and $160^{\circ}C$) and 30 minute assembly times for four adhesive mixing types. Evaluations of the LDPE addition were carried out by performance tension shear tests after two cycle boil aging tests on plywood per the U.S. Product Standard PS I-83. After accelerated-aging tests. plywoods were exhibited no delamination. The test results included tension shear strength and estimated wood failure values. The plywood test results support the use of polyethylene as an additive in plywood adhesives.