가교 폴리우레탄 망상구조의 특성에 관한 연구

허만규; 곽종명; 허탁

Polymer(Korea), Vol.20, No.3, 392-402, May, 1996

Export Citation

가교 폴리우레탄 망상구조의 특성에 관한 연구

A Study on the Characteristics of Network Structures of Crosslinked Polyurethanes

허만규, 곽종명, 허탁

초록

Poly(propylene glycol), trimethylol propane, 4,4'-diphenylmethane diisocyanate와 같은 원료의 조성을 변화시켜서 가교밀도, 가교점의 분포, 가교구조의 결함 등과 같은 망상구조 특성이 서로 다른 일련의 가교 폴리우레탄을 합성하였다. 사슬이 화학적인 가교점 사이에 영원히 갇혀있는 물리적인 가교의 기여는 화학적인 가교밀도가 증가할수록 그리고 가교점의 분포가 균일하지 않을 때 증가하였다. 인장강도와 같은 기계적인 성질은 예상했던 바와 같이 가교밀도가 높아질수록 증가하였다. 유리전이온도는 총가교밀도가 증가할수록 높은 값을 보였으며 , 동일한 가교밀도에서는 미반응 매달진 사슬이 존재하고 가교점의 분포가 불균일할 경우에 상승하였다. 한편, 크리프 현상과 같은 점탄성 거동은 유리전이온도를 기준으로 하여 정상화시킨 후에 비교하여 본 결과 화학적인 가교나 물리적인 가교의 상대적인 기여도에 상관없이 총가교밀도에 의존함을 발견할 수 있었다.

A series of crosslinked polyurethanes with different network structures such as crosslinking density, distributions of crosslink junctions, and network defects were prepared, varying stoichiometry and compositions of poly(propylene glycol), trimethylol propane, 4,4'-diphenyl methane diisocyanate. The relative contribution of physical crosslinks which are permanent entanglements between elastically effective crosslink junctions increased with higher chemical crosslinking density and nonuniform distribution of crosslink junctions. As expected, mechanical strengths such as tensile strength increased as crosslinking densities increased. Higher total crosslinking density shifted the glass transition temperature to a higher position. Under the same crosslinking densities, the existence of unreacted dangling chains and nonuniform distribution of crosslink Junctions resulted in high glass transition temperatures. In addition, when the temperature of each sample are normalized to each glass transition temperature, viscoelastic behavior such as creep phenomenon depended on the total crosslinking density regardless of relative contribution of either chemical crosslinks or physical crosslinks.

Keywords:network;network defects;physical crosslinks;chemical crosslinks

[References]

Dusek K, MacKnight WJ, "Crosslinked Polymers," R.A. Dickie, S.S. Labana, and R.S. Bauer, Eds., ACS Symp. Ser. No. 367, ACS, Washington, D.C. (1988)
Dusek K, Ilavsky M, Stokrova S, "Crosslinked Epoxies," B. Sedlacek and J. Kahovec, Eds., Berlin (1987)
Gordon M, RossMurphy SB, Pure Appl. Chem., 43, 1 (1975)
Dusek K, Br. Polym. J., 17(2), 185 (1985)
Dusek K, Adv. Polym. Sci., 78, 1 (1986)
Flory PJ, Chem. Rev., 35, 51 (1944)
Scanlan J, J. Polym. Sci., 43, 501 (1960)
Case LC, J. Polym. Sci., 45, 397 (1960)
Saunders JH, Frisch KC, "Polyurethanes: Chemistry and Technology," 4th Ed., Wiley-Interscience, New York (1979)
Hur T, Manson JA, Sperling LH, J. Polym. Sci., 27, 2251 (1989)
Spierling LH, "Introduction to Physical Polymer Science," 2nd Ed., Wiley-Interscience, New York (1992)
Yeo JK, Sperling LH, Thomas DA, J. Appl. Polym. Sci., 26, 3977 (1981)
Smith CP, Reisch JW, Connor JMO, Polyurethane World Congress, 313 (1991)
Manno PJ, "Urethane Chemistry and Applications," K.N. Edwards, Ed., ACS Symp. Ser. No. 172, ACS, Washington, D.C. (1981)
Foss RP, Tam W, Zumsteg FC, Polym. Prepr., 32, 76 (1991)
Marsh HE, Chung SY, Hsu GC, Wallace CJ, "Chemistry and Properties of Crosslinked Polymers," S.S. Labana, Ed., Academic Press, New York (1977)
Case LC, "Biological and Synthetic Polymer Networks," O. Kramer, Ed., Elsevier Applied Science, New York (1988)
Pearson DS, Graessley WW, Macromolecules, 13, 1001 (1980)
Ilavsky M, Dusek K, Polymer, 24, 981 (1983)
Charlesby A, Proc. Roy. Soc., A222, 542 (1954)
Hogkin JH, Martinelli FJ, Heller J, Marsh HE, Polym. Prepr., 12(1), 598 (1971)
Langley NR, Macromolecules, 1, 348 (1968)
Aharoni SM, Edwards SF, Macromolecules, 22, 3361 (1989)
Langley NR, Polmanteer KE, J. Polym. Sci. B: Polym. Phys., 12, 1023 (1974)
McCrum NG, Buckley CP, Bucknall CP, "Principles of Polymer Engineering," Oxford University Press, New York (1988)
Maconnachie A, Allen G, Richards RW, Polymer, 22, 1157 (1981)

[Referenced By]

[1] Dusek K, MacKnight WJ, "Crosslinked Polymers," R.A. Dickie, S.S. Labana, and R.S. Bauer, Eds., ACS Symp. Ser. No. 367, ACS, Washington, D.C. (1988)

[2] Dusek K, Ilavsky M, Stokrova S, "Crosslinked Epoxies," B. Sedlacek and J. Kahovec, Eds., Berlin (1987)

[3] Gordon M, RossMurphy SB, Pure Appl. Chem., 43, 1 (1975)

[4] Dusek K, Br. Polym. J., 17(2), 185 (1985)

[5] Dusek K, Adv. Polym. Sci., 78, 1 (1986)

[6] Flory PJ, Chem. Rev., 35, 51 (1944)

[7] Scanlan J, J. Polym. Sci., 43, 501 (1960)

[8] Case LC, J. Polym. Sci., 45, 397 (1960)

[9] Saunders JH, Frisch KC, "Polyurethanes: Chemistry and Technology," 4th Ed., Wiley-Interscience, New York (1979)

[10] Hur T, Manson JA, Sperling LH, J. Polym. Sci., 27, 2251 (1989)

[11] Spierling LH, "Introduction to Physical Polymer Science," 2nd Ed., Wiley-Interscience, New York (1992)

[12] Yeo JK, Sperling LH, Thomas DA, J. Appl. Polym. Sci., 26, 3977 (1981)

[13] Smith CP, Reisch JW, Connor JMO, Polyurethane World Congress, 313 (1991)

[14] Manno PJ, "Urethane Chemistry and Applications," K.N. Edwards, Ed., ACS Symp. Ser. No. 172, ACS, Washington, D.C. (1981)

[15] Foss RP, Tam W, Zumsteg FC, Polym. Prepr., 32, 76 (1991)

[16] Marsh HE, Chung SY, Hsu GC, Wallace CJ, "Chemistry and Properties of Crosslinked Polymers," S.S. Labana, Ed., Academic Press, New York (1977)

[17] Case LC, "Biological and Synthetic Polymer Networks," O. Kramer, Ed., Elsevier Applied Science, New York (1988)

[18] Pearson DS, Graessley WW, Macromolecules, 13, 1001 (1980)

[19] Ilavsky M, Dusek K, Polymer, 24, 981 (1983)

[20] Charlesby A, Proc. Roy. Soc., A222, 542 (1954)

[21] Hogkin JH, Martinelli FJ, Heller J, Marsh HE, Polym. Prepr., 12(1), 598 (1971)

[22] Langley NR, Macromolecules, 1, 348 (1968)

[23] Aharoni SM, Edwards SF, Macromolecules, 22, 3361 (1989)

[24] Langley NR, Polmanteer KE, J. Polym. Sci. B: Polym. Phys., 12, 1023 (1974)

[25] McCrum NG, Buckley CP, Bucknall CP, "Principles of Polymer Engineering," Oxford University Press, New York (1988)

[26] Maconnachie A, Allen G, Richards RW, Polymer, 22, 1157 (1981)