05-47(2)-04(김영호).fm
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1 w œwz, 47«2y 2010 Textile Science and Engineering Vl. 47, N. 2, 2010 š w Ply(phenylene sulfide) v p y w Á½ y w» Áq œw ( / k) Effect f High Temperature Annealing n the Prperty Changes f Ply(phenylene sulfide) Films Myng J Ham and Yung H Kim Department f Organic Materials and Fiber Engineering, Sngsil University, Seul , Krea (Received February 10, 2010/Accepted April 9, 2010) Abstract: Amrphus ply(phenylene sulfide) (PPS) films were prepared by melt-pressing virgin PPS chips f high linearity and quenching int ice water. The films were annealed at 240 C fr up t 17 days and investigated by using a DSC. Bth the melting temperature and heat f melting f PPS increased with increasing annealing time at 240 C, whereas the melt crystallizatin temperature and heat f melt crystallizatin decreased. Althugh the melting peak n heating still appeared, the melt crystallizatin peak n cling disappeared after mre than 10 days annealing, indicating the intrductin f high degree f crss-linking. FTIR analysis and slubility tests f the annealed films als suggested the intrductin f crsslinking. Increased crsslinking density refrained PPS frm melt crystallizatin and disslutin in a slvent. Annealing at lwer temperature such as 160 C fr up t 24 hurs resulted in increasing the tensile strength f the films significantly withut crsslinking. The chemical resistance f the films was almst unaffected in strng acid and alkaline slutins at 93 C fr 7 days. Keywrds: ply(phenylene sulfide) (PPS) film, high temperature annealing, thermal prperty, crsslinking, tensile strength 1. š w,», ü w ü» w w» w ƒ.,»á,» t, wœ w š» š v š, ww š w ƒ f š. ply(phenylene sulfide) (PPS) ü üyw ù š, t v p wù. PPS y ƒ q ey xk w š, š» š ƒ ƒ. PPS ü t w» ùküš, ù ƒ š ù ù yƒ ƒ w,» ù š, xk w [1,2]. w, 200 C w w, 200 C ƒ Crrespndence t Yung H Kim ([email protected]) 2010 The Krean Fiber Sciety /2010-2/ w yw w ü w w ü t ùkü [3] Phillips Petrleum Edmnds Hill w Scheme 1 p-dichlrbenzene sdium sulfide w PPS w t [4,5], w» w ù v ƒ ƒ w Phillips PPS Rytn t q w» w, 1983 Phillips Fibers Crps w y [6]. x PPS w Ticna, Tray, Kureha, DIC, š DeYang. PPS ü t» ƒ vl, š, e p w š,» ƒwš. ù PPS ƒ» ¾ w w Scheme 1. Phillips prcess fr the slutin plymerizatin f PPS. 102
2 š w Ply(phenylene sulfide) v p y 103 š. w, PPS f» w» š w Á» û. w w» w PPS ù k w xk š ù, z t œ ƒ» w š [7]. PPS w y w PPS/ w [8,9] PPS/ ƒ š [10-12] w š. w PPS ü w» w ƒ ƒ, w PPS w ü wš t w ƒ y w š. PPS w w» w x (linearity) w w. PPS» Phillips w w ƒ ƒ ù ƒ xk ƒ [13] w ww., ¾ w PPS š ƒ ù d w x š. x š PPS ƒ w œ w. ù ¾ x PPS ù v w»ƒ. ¾ ƒ y w wì PPS ù v w p yw»ƒ» q. ü PPS w v w» œw» w. w»ƒ» v p w. w š w ƒ š w v w w. PPS w» w v e PPS š ƒ p w. w PPS t, p š, w p w. w p y» w PPS v g p y w š, v ƒyw g» p üyw y w PPS w š w. 2. x 2.1. PPS Ticna ƒ 1.35 g/cm 3 100% PPS (virgin PPS) w. 300 C k z þ g Ì 200 µm x v w w, v 240 C 17 ¾ 160, 180, 200 C 24 ¾ k z w. 1-chlrnaphthalene Aldrich t w, y,, yùp 1 w Perkin Elmer Diamnd DSC w» w 10 C/min p w, TG/DTA(Seik, TG/DTA 6200) w» w 20 C/min w d w. w Seik DMS 210 w» 400 mn, 1 Hz w 2 C/min k p d w FT-IR v ATR e 256, reslutin 4 cm 1 w FT-IR rp. 2.4.» p d Universal Testing Machine(Hunsfield H10KS, UK) w v ASTM D 638 w d w. speed 10 mm/min w š ƒ 10z d w s³ w üyw w v ASTM D 543 w, 93 C 30% NaOH, 30% HCl, 30% H 2 SO 4 10% HNO 3 1 e k z wš d w, w. 3. š 3.1. PPS v p PPS 300 C 1 jš w z þ g Ì 200 µm PPS v w. PPS v n w, 300 C 1 þ w x k. wr, v j ¼ w š n ƒ û yƒ û dw. PPS ƒ š, š š» w ù s w». PPS Textile Science and Engineering, Vl. 47, N. 2, 2010
3 104 w Á½ y Figure 1. DSC (a) heating curve f PPS film prepared frm melt-quenching methd and (b) cling ne frm the mlten state at 300 C. š d ƒ» w, q š PPS (T m ) 280 C š (T g ) 90 C š š [14]. w, ü w [15,16] w ùkü. w x PPS v DSC g š 300 C DSC 5 k z þƒw š Figure 1 ùkü. 300 C 5 j ƒ wƒ ú ƒ f 5 w. Figure 1(a) 90.8 C T g ƒ ùkùš, C þ y (T cc )ƒ, C T m ùkû. T g T m xe[14] w ù w. wr, k z þƒ ùkù y (T mc ) C. T g T cc ƒ z þ w x PPS v wì x w. x ùkù PPS 100% w 80.4 J/g [17]. l w y 41.5%, 54.1%, 10 C/min w. Figure 2 PPS v tan δ š y DMA d w ùkü. k (E') š 93 C w w ùküš, (E") š 96 C ƒ w, Figure 2. (a) Strage mdulus (E'), (b) lss mdulus (E"), and (c) tan δ curve f hm PPS film prepared frm meltquenching methd. tan δ w 100 C ƒ wš w w. x k PPS v ƒ ƒ ƒ E" š vj ùkù. wr, tan δ š 120~150 C shulder xk vjƒ ùkù, 140 C E' š w ƒ wì E'' š vjƒ ùkù, š x k š ƒ y ùkù x., DSC þ y w w vj š w. d DMA š ù kù š ù þ y w vj DSC ùkù 10~20 C š ùkù, x w ew. PPS w»» w ƒ w. t xk t xkƒ». PPS ƒ jš ƒ w š. w PPS š ƒ ƒ. ù ƒ d w š, w w w ƒ q w., w PPS ƒ ƒ w ƒ w ƒ j», w š PPS w ƒ w q w. Scheme 1 ùkü PPS C-C( ), C-H, w œwz, 47«2y 2010
4 고온 열처리에 의한 Ply(phenylene sulfide) TGA curves f hm PPS film in (a) nitrgen and (b) air atmsphere. Figure 3. C-S 결합으로 이루어져 있으며, 각 결합의 해리에너지(bnd dissciatin energy)는 kj/ml, kj/ml, kj/ml로 높은 값을 갖는다[4]. 이 때문에 PPS는 다른 범 용 고분자보다 높은 열분해 온도를 나타낸다. PPS 시료의 열분해 거동을 알아보기 위하여 20 C/min의 승온속도로 측정한 TGA 곡선을 나타낸 것이 Figure 3이다. 일반 범용 고분자의 열분해 개시온도가 약 400 C 정도인데 비하여, PPS 필름의 열분해 개시온도는 질소와 공기 기류 모두에 600 C 서 500 C 정도로 높게 나타났다. 공기 기류 하에서는 이상에서 무게유지율이 급격히 감소하고 700 C 정도에서 모두 분해되었지만, 질소 기류 하에서는 분해가 조금 먼저 시작되기는 하지만 700 C 이상에서 약 30%의 무게유지율 을 나타내어 잔존 물질이 많음을 알 수 있다. 고온에서 열처리한 필름의 특성 변화 용융시킨 PPS 고분자를 공기 중에서 계속 열처리하면 용 융물이 검게 변하고 이어서 겔화 및 고화된다. 이 고체 고 분자는 높은 온도에서도 모든 유기용매에 용해되지 않기 때문에 PPS가 가교되었다고 판단한다. 용융 상태까지는 아 니더라도 PPS를 고온에서 열처리하면 가교되어 분자량이 증가한다. 상업적으로 판매되는 PPS의 분자량은 약 50,000 g/ml 정도이지만, 1차 생산된 PPS 수지의 분자량은 그렇 게 크지 않다. 다소 가교가 생기더라도 분자량을 높이는 것 이 중요하기 때문에 PPS를 용융온도 부근에서 열처리하는 경우가 있는데, 이 공정을 보통 큐어링(curing) 공정이라고 하고 얻어진 고분자는 큐어링된 고분자(cured plymer)라 고 한다[13]. 큐어링에 의해 PPS는 분자량 증가, 용매에 대 3.2. 필름의 특성 변화 105 한 용해도 감소, 인성 증가, 용융점도 증가(용융지수 감소), 결정화도 감소, 백색에서 검은 갈색으로의 색상 변화 등과 같은 변화가 일어난다[18]. 그러나 이 공정에 의한 가교와 극히 제한적인 용해성 때문에 이 반응의 메카니즘을 정확 히 아는 것은 거의 불가능하다. 큐어링에 의한 변화 정도 는 처리 시간 및 온도와 같은 큐어링 조건에 따라 달라지 며, 큐어링된 PPS가 버진 PPS에 비해 훨씬 강력이 크고 강인할 뿐만 아니라 사출성형 및 압축성형 공정이 쉽기 때 문에 큐어링시킬 수 있는 것이 PPS 고분자의 가장 중요한 특성 중의 하나이다. 본 연구에서는 PPS 필름을 고온에서 장시간 열처리하는 경우 열적 특성들이 어떻게 변하는 가를 제시하고자 하였 다. 이러한 특성을 파악하면 PPS를 섬유로 제조하여 백 (bag) 필터와 같은 제품을 제조한 후 제품 상태에서 큐어 링함으로써 내열성을 더 향상시키는데 도움이 될 것으로 판단된다. 즉, 용융이 되는 PPS 섬유로 제품을 제조한 후 고온에서 열처리시켜 가교시킴으로써 용융되지 않게 하여 내열성을 향상시킬 수 있을 것이다. Figure 4는 Figure 1의 Tm(278.4 C) 보다는 낮지만 Tcc (123.7 C) 보다는 훨씬 높은 240 C에서 서로 다른 시간 (1~17일) 동안 열처리한 PPS 필름들의 사진을 나타낸 것 이다. 열처리 전의 무정형 PPS 필름은 거의 투명하였지만, 열처리 시간이 길어짐에 따라 큐어링 효과가 나타나 점차 불투명해지면서 검은 갈색으로 변하였다. PPS Textile Science and Engineering, Vl. 47, N. 2, 2010 Images f the PPS films annealed at 240 C fr (a) 0, (b) 1, (c) 3, (d) 5, (e) 7, (f) 10, and (g) 17 days. Figure 4.
5 106 w Á½ y Figure 5. DSC (A) heating curves f PPS film annealed at 240 C fr (a) 0, (b) 1, (c) 3, (d) 5, (e) 7, (f) 10, and (g) 17 days and (B) their cling curves frm the mlten state. w ƒ w wì y p j w q, DSC w Figure 5 ùkü. š, ùkù T g T cc ƒ ùkù y. w T m vjƒ š j ùkù w jš ³ w. wr, ¼ T m š ƒw 17 k v 295 C vjƒ ùkù w 17 Cù ƒw. wr DSC k z þƒ j Figure 5(B) Figure 6. Changes in (A) T m and T mc and (B) enthalpy change f melting and melt crystallizatin f annealed PPS films as a functin f annealing time at 240 C., 240 C 1 w T mc ƒ w ƒw, w 10 w T mc ƒ ùkù. Figure 5 T m T mc w Figure 6(A) ùkü. w DSC š ( H m ) y ( H mc ) w Fgure 6 ùkü. Figure 6(A) ƒw T m ƒw. 1 w ùkü. T m ƒ ¼ w ƒ ù, ƒ w w w œwz, 47«2y 2010
6 ùkù. Figure 5(A) 1 w š j vj ùkü, w ƒ w» ƒ» w š q. T mc y l. Figure 6(A) ¼ T mc ƒw ƒ j w. 1 w PPS š w x w vj ù kù, Figure 4 ƒ w wì š w ƒ w wƒ. w w ƒ w z þƒ w w T mc ƒ w. ù w ƒ ƒ f š T m š T mc j û. 10 ¼ ƒ ùkù, š ù þƒ w w T mc ƒ ùkù. w w H m H mc y., 10 ¾ ã ƒ. ƒ w w. ù y ƒw j w ƒ 10 ¼ yƒ ù. y ¼ ƒwš y w, š w w ƒ w z w». š w y r» w š w v ATR-FTIR d w rp Figure 7 ùkü. x š PPS IR p vj p-phenylene sulfur stretching skeletal benzene, p-phenylene sulfur stretching PPS x w w [19-21]. Figure 7, w PPS v rp skeletal benzene ƒ 1468 cm 1, 1008 cm 1, š 740 cm ƒƒ 1 ùkû, p-phenylene sulfur stretching 1091 cm cm 1 ùkû. PPS v w ¼ vj j»ƒ w, 240 C 17 w p-phenylene sulfur stretching skeletal benzene j»ƒ j y w. Scheme 2 j w PPS š w Ply(phenylene sulfide) v p y 107 Figure 7. ATR-FTIR spectra f PPS films annealed at 240 C fr (a) 0, (b) 1, (c) 3, (d) 5, (e) 7, (f) 10, and (g) 17 days. Scheme 2. Crsslinking mechanism f PPS during the curing prcess [19]. ƒ e ùkü [20]. š w PPS phenylene ƒ ƒ š ƒ w q 2ey w p-phenylene sulfur stretching skeletal benzene j»ƒ w q. IR rp q 2ey w, 3ey ƒ ƒ y w. wr, PPS 200 C ƒ w yw w w. ƒ t ƒ 1- chlrnaphthalene. w ƒ w y w» w w v 210 C 1-chlrnaphthalene w w xw. w PPS v 210 C 1- chlrnaphthalene w, ¼ ƒ w 240 C 5 w 210 C 1-chlrnaphthalene w. w x l š w Textile Science and Engineering, Vl. 47, N. 2, 2010
7 108 w Á½ y PPS ƒ ƒ x y w w ü t y Figure 4~7 w 240 C w ƒ ƒ š wƒ ù. û PPS v w wù ƒ ƒ k. y w» w 160~200 C û 24 ü PPS v w d w, w y y g Figure 8 ùkü. w 200 µm w Ì, 10z d w w s³ w. PPS v 54.6 MPa ùkü, w 80 MPa ƒw. ƒ š ƒ» w, 3 ü w 200 C 160 C 180 C w ƒw š q w. Figure 1 T cc ƒ 124 C š w ƒ ƒ w. 6 w ƒ ƒw x ùkù» w x q, 6 ¼ w ù kü š. w 160 C Figure 8. Changes in tensile strength f PPS films annealed at (a) 160 C, (b) 180 C, and (c) 200 C fr different times. Table 1. Tensile strength retentin f the PPS films measured after immersing in aqueus alkaline r acidic slutin at 93 C fr ne week * Aqueus slutin fr immersin Tensile strength retentin f PPS film (%) 30% H 2 SO 4 30% HCl ƒ ww. PPS ƒ j ü t. ü t y w» w PPS v 93 C 30% NaOH, 30% HCl, 30% H 2 SO 4 10% HNO 3 1 e k z, w w Table 1 ùkü. PPS w w w» w 160 C 1 k v w. w y y z w e». w PPS v 93 C 30% NaOH, 30% HCl, 30% H 2 SO 4 1 w 90% ùk ü, 10% HNO 3 50% ùkü. 93 C 1 e š w PPS v w» e w ü t % 30% HNO 3 NaOH *PPS films were annealed at 160 C fr 1 hur prir t the treatment. PPS 300 C g 200 µm Ì v w z» wš, 240 C 160~200 C w w. z þ k x T g ƒ 90.8 C, T cc C, T m C, z T mc C š, w. PPS v 240 C w j w» w w. 240 C j T m ƒwš vj w y ƒw. ¼ T m ƒw H m 7 w, T mc H mc j w 10 w x w w. DSC š, FTIR rp 1-chlrnaphthalene w w, 240 C w w œwz, 47«2y 2010
8 š w Ply(phenylene sulfide) v p y 109 PPS ƒ w y w. PPS v 160~200 C 1 w wù ƒ 50~60% ƒ k. 160 C 1 k PPS v 93 C 30% NaOH, 30% HCl 30% H 2 SO 4 1 w 90% w ü ü e ùkü. š x 1. J. P. Critchley, W. W. Wright, and G. J. Knight, Heat Resistant Plymer, Plenum Press, NY, 1984, pp J. W. S. Hearle, Ed., High-Perfrmance Fibres, Wdhead Publishing Ltd., USA, 2001, pp J. K. Fink, High Perfrmance Plymers, William Andrew Inc., USA, 2008, pp J. F. Geibel and J. E. Leland, Kirk-Othmer Encyclpedia f Chemical Technlgy, Jhn Wiley & Sns, New Yrk, 1996, 4th Ed., pp J. F. Geibel and R. W. Campbell, Cmprehensive Plymer Science, Pergamn Press, Oxfrd, 1990, p Y. H. Kim and J. C. Kim, Develpment and Applicatins f Ply(phenylene sulfide) Fibers, Fiber Tech Ind, 2007, 11, J. P. Critchley, W. W. Wright, and G. J. Knight, Heat Resistant Plymer, Plenum Press, NY, 1984 pp J. Ca and L. Chen, Effect f Thermal Cycling n Carbn Fiber-Reinfrced PPS Cmpsite, Plym Cmps, 2005, 26, T. Sinmazcelik, Natural Weathering Effects n the Mechanical and Surface Prperties f Plyphenylene Sulphide (PPS) Cmpsites, Materials and Design, 2006, 27, T. Hisamatsu, S. Nakan, T. Adachi. M. Ishikawa, and K. Iwakura, The Effect f Cmpatibility n Tughness f PPS/ SEBS Plymer Ally, Plymer, 2000, 41, K. Kub and J. Masamt, Dispersin f Ply(phenylene ether) in a Ply(phenylene sufide)/ply(phenylene ether) Ally, Macrml Mater Eng, 2001, 286, W. Tang, X. Hu, J. Tang, and R. Jin, Tughening and Cmpatibilizatin f Plyphenylene Sulfide/Nyln 66 Blends with SEBS and Maleic Anhydride Grafted SEBS Triblck Cplymers, J Appl Plym Sci, 2007, 106, S. Russ, Ed., Cmprehensive Plymer Science, Pergamn Press, 1989, Vl. 5, pp W. Gerhartz, Ed., Ullmann's Encyclpedia f Industrial Chemistry, Wiley-VCH, 1985, Vl. A21, pp K. Mai, Z. Mei, J. Xu, and H. Zeng, Effect f High- Perfrmance Plymers n Crystallizatin and Multiple Melting Behavir f Ply(phenylene sulfide), J Appl Plym Sci, 1998, 69, K. Mai, Z. Mei, J. Xu, and H. Zeng, Effect f Blending n the Multiple Melting Behavir f Plyphenylene Sulfide, J Appl Plym Sci, 1997, 63, J. E. Mark, Ed., Plymer Data Handbk, Oxfrd University Press, NY, 2009, pp R. B. Seymur and G. S. Kirshenbaum, Ed., High Perfrmance Plymers: Their Origin and Develpment, Elsevier Science Publishing C., NY, 1986, pp E. Tsuchida, E. Shuji, and K. Yamamt, Synthesis f High Mlecular Weight Ply(phenylene sulfide) by Oxidative Plymerizatin via Ply(sulfnium catin) frm Methyl Phenyl Sulfxide, Macrmlecules, 1993, 26, E. Tsuchida, K. Yamamt, H. Nishide, S. Yshida, and M. Jikei, Plymerizatin f Diphenyl Disulfide by the S-S Bnd Cleavage with a Lewis Acid: A Nvel Preparatin Rute t Ply(p-phenylene sulfide), Macrmlecules, 1990, 23, Textile Science and Engineering, Vl. 47, N. 2, 2010
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