Precoated Metal용 Copolyester Resin의 합성 및 물성

박이순; 이태형; 김순학; 장진규

Journal of the Korean Industrial and Engineering Chemistry, Vol.10, No.3, 427-431, May, 1999

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Precoated Metal용 Copolyester Resin의 합성 및 물성

Synthesis and Properties of Copolyester Resin for Precoated Metal

박이순, 이태형, 김순학, 장진규

초록

알루미늄 혹은 철판의 코일 코팅 (coil coating) 공정에 사용되는 기본 수지인 copolyester의 중합 방법 및 생성된 copolyester의 분자량, 열적 성질 및 용해 특성에 대해 조사를 하였다. Copolyester 수지의 합성은 1단계 반응에서 bishydroxyethyl terepthalate (BHET), bishydroxyneopentyl terephthalate (BHNPT), bishydroxyethyl isophthalate (BHEI), bishydroxyneopentyl sebacate (BHNPS), bishydroxyneopentyl adipicate (BHNPA), bishydroxyethyl adipicate (BHEA) 올리고머를 esterification 반응을 통해 얻고 이들을 적정 mole 비로 혼합한 다음 polycondensation 반응을 시키는 2단계 반응으로 진행시켜 GPC로 측정된 중량 평균 분자량이 30,000∼59,000 g/mole의 범위에 있는 비교적 고분자량의 copolyester를 얻을 수 있었다. 합성된 copolyester 시료들은 모두 T_m을 나타내지 않아 비결정성 수지임을 알 수 있었고 이것은 고분자 주쇄 내에 kink 구조를 유발하는 BHEI와 bulky한 neopentyl 연결기를 가지는 BHNPT, BHNPS와 같은 올리고머를 포함하는데 기인한 것으로 생각되었다. Copolyester 시료 중에서 BHEI (0.3 mole), BHNPS (0.1 mole)올리고머를 같은 비율로 유지하고 BHET의 약 반 정도를 benzene 환 내에 같은 para 연결 구조를 가지나 bulky한 neopentyl glycol로 치환된 BHNPT로 바꾸어줌으로서 40℃ 이상의 비교적 높은 T_g를 유지하면서 상온 및 저온 (-5℃)에서 톨루엔 용매에 용해성이 높은 copolyester수지를 얻을 수 있었다.

Copolyester resins for the coil coating porcess of aluminium and steel strip were synthesized and their thermal properties, molecular weight and solvent solution characteristics were examined. Copolyesters were obtained by two step reactions. The first step was to prepare bishydroxyethyl terephthalate (BHET), bishydroxyneopentyl terephthalate (BHNPT), bishydroxyethyl isophthalate (BHEI), bishydroxyneopentyl sebacate (BHNPS), bishydroxyneopentyl adipicate (BHNPA) and bishydroxyethyl adipicate (BHEA) oligomers by esterification reaction. The second step was the polycondensation reaction utilizing those oligomers to obtain relatively high molecular weight copolyesters (Mw = 30,000∼59,000 g/mol) as measured by GPC. These copolyesters were amorphous polymers as shown by DSC without T_m peaks probably due to the kink structure introduced by BHET oligomer and relatively large free volume by bulky BHNPT and BHNPS oligomers. The copolyester samples with half of BHET oligomer substituted by BHNPT while keeping BHEI (0.3 mole) and BHNPS (0.1 mole) ratio constant showed glass transition temperature above 40℃ and good solubility in toluene both at low (-5 ℃) temperature and room temperature.

Keywords:Coil Coating;PCM (precoated metal);Thermal Properties;Copolyesters

[References]

"Coatings, V" Skeist Incorporated, 281 (1992)
Calbo LJ, "Handbook of Coatings Additives," Marcel Dekker, 307 (1987)
"Encyclopedia of Polym. Sci. and Eng.," John Wiley & Sons, Vol. 12, 217 (1988)
Pocius AV, "Adhesive and Adhesive Technology," Hanser, 167 (1997)
Lang E, "Coatings for High Temperature Application," Elsevier Science, New York, 73 (1983)
Onishi Y, Nakai T, Polym. J., 24, 833 (1992)
Nichols ME, Roberton RE, J. Polym. Sci. B: Polym. Phys., 30, 755 (1992)
Marrs W, Peters RH, Still RH, J. Appl. Polym. Sci., 23, 1063 (1979)
U.S. Patent, 3,426,098 (1969)
U.S. Patent, 4,362,861 (1969)
Landrock AH, "Adhesives Technology Handbook," Noyes Publications, 1 (1985)
Park LS, Yoon JH, Polym.(Korea), 18(5), 700 (1994)
Park LS, Hwang JS, Lee DC, Polym.(Korea), 19(5), 668 (1995)
Park LS, Do JH, Lee DC, J. Appl. Polym. Sci., 60(12), 2059 (1996)

[1] "Coatings, V" Skeist Incorporated, 281 (1992)

[2] Calbo LJ, "Handbook of Coatings Additives," Marcel Dekker, 307 (1987)

[3] "Encyclopedia of Polym. Sci. and Eng.," John Wiley & Sons, Vol. 12, 217 (1988)

[4] Pocius AV, "Adhesive and Adhesive Technology," Hanser, 167 (1997)

[5] Lang E, "Coatings for High Temperature Application," Elsevier Science, New York, 73 (1983)

[6] Onishi Y, Nakai T, Polym. J., 24, 833 (1992)

[7] Nichols ME, Roberton RE, J. Polym. Sci. B: Polym. Phys., 30, 755 (1992)

[8] Marrs W, Peters RH, Still RH, J. Appl. Polym. Sci., 23, 1063 (1979)

[9] U.S. Patent, 3,426,098 (1969)

[10] U.S. Patent, 4,362,861 (1969)

[11] Landrock AH, "Adhesives Technology Handbook," Noyes Publications, 1 (1985)

[12] Park LS, Yoon JH, Polym.(Korea), 18(5), 700 (1994)

[13] Park LS, Hwang JS, Lee DC, Polym.(Korea), 19(5), 668 (1995)

[14] Park LS, Do JH, Lee DC, J. Appl. Polym. Sci., 60(12), 2059 (1996)