PC/ASA blends having enhanced interfacial and mechanical properties

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1 Krea-Australia Rhelgy Jurnal Vl. 18, N. 1, March 2006 pp. 1-8 PC/ASA blends having enhanced interfacial and mechanical prperties M. S. Kang, C. K. Kim* and J. W. Lee 1 Schl f Chemical Engineering & Materials Science, Chung-Ang University, 221 Huksuk-Dng, Dngjak-Gu, Seul , Krea 1 Department f Chemical Engineering, Sgang University, Seul , Krea (Received July 29, 2005; final revisin received Nvember 15, 2005) Abstract Blend f bisphenl-a plycarbnate (PC) and (acrylnitrile-styrene-acrylic rubber) terplymer (ASA) having excellent balance in the interfacial prperties and mechanical strength was develped fr the autmbile applicatins. Since interfacial adhesin between PC and styrne-acrylnitrile cplymer (SAN) matrix f ASA is nt strng enugh, tw different types f cmpatibilizers, i.e, diblck cplymer cmpsed f tetramethyl plycarbnate (TMPC) and SAN (TMPC-b-SAN) and ply(methyl methacrylate) (PMMA) were examined t imprve interfacial adhesin between PC and SAN. TMPC-b-SAN was mre effective than PMMA in increasing interfacial adhesin between PC and SAN matrix f ASA (r weld-line strength f PC/ASA blend). When blend cmpsitin was fixed, PC/ASA blends exhibited similar mechanical prperties except impact strength and weld-line strength. Impact strength f PC/ASA blend at lw temperature was influenced by rubber particle size and its mrphlgy. PC/ASA blends cntaining cmmercially available PMMA as cmpatibilizer als exhibited excellent balance in mechanical prperties and interfacial adhesin. Keywrds : plycarbnate, (acrylnitrile-c-styrene-c-acrylic rubber) terplymer, interfacial strength, impact strength, mrphlgy 1. Intrductin Even thugh bisphenl-a plycarbnate (PC) is using in a wide variety f applicatins because f its excellent balance f prperties, applicatin f PC ften deterred because f its pr characteristics such as thickness dependence f ntched impact strength, pr slvent and hydrlysis resistance, and pr ultravilet stability (Freitag et al., 1988). T vercme deficient characteristics f PC, acrylnitrile-butadiene-styrene terplymer (ABS) was blended with PC. Blends f PC with ABS materials is widely used cmmercially because these blends prvide prducts having imprved balance f prperties at reduced cst in cmparisn t PC (Freitag et al., 1988; Guest and Daly, 1989; Keitz et al., 1984; Paul et al., 1988; Quentens et al., 199. Hwever, applicatin f the typical PC/ABS blends als ften limited because f their fllwing drawbacks. Since interfacial adhesin between PC and acrylnitrilestyrene cplymer (SAN) matrix f ABS is nt strng enugh, PC/ASA blend exhibited pr adhesin at weld (Callaghan et al., 1993; Cheng et al., 1992; Kang et al., 2000; Kim et al., 1992; Kim et al., 2001; Wl, 1989). *Crrespnding authr: ckkim@cau.ac.kr 2006 by The Krean Sciety f Rhelgy Butadiene rubber cntaining duble bnd in its repeat unit underwent physical r chemical aging caused by ultravilet (UV) radiatin during the utdr applicatins (Cheng et al., 1992). Aging f butadiene rubber resulted in cntinuus decline in the mechanical strength and clr changes f blend. Applicatin f the PC/ABS blends culd be bradened by imprving interfacial adhesin between PC and SAN matrix as well as by remving aging prblems f the butadiene rubber. Aging prblems in the butadiene rubber culd be slved by using acrylnitrile-styrene-acrylic rubber terplymer (ASA) instead f ABS (Wrks, 1996). Nte that acrylic elastmer, i.e., plybutylacrylate des nt cntain duble bnd in its repeat unit. Prblems f the interfacial adhesin between PC and SAN matix f ABS culd be als slved by adding prper cmpatibilizer (Kang et al., 2000; Kim et al., 2001; Wrks, 1996). Even thugh it was knwn that ASA exhibited excellent UV stability, prperties f PC/ ASA blend such as impact strength at lw temperature and tensile elngatin were prer than thse f PC/ABS blend. In this study, varius ASA terplymers, in which rubber particles are different in size and shape, were examined t slve prblems in the mechanical prperty f PC/ ASA blends. Cmpatibilizer was added t PC/ASA blends t enhance Krea-Australia Rhelgy Jurnal March 2006 Vl. 18, N. 1 1

2 M. S. Kang, C. K. Kim and J. W. Lee interfacial adhesin between PC and SAN matrix f ASA. In here, TMPC-b-SAN and PMMA were examined as cmpatibilizer. In the previus researches (Kim et al., 200, we have explred TMPC-b-SAN fr the cmpatibilizer f the PC/SAN blend. It was knwn that TMPC-b- SAN was the mst effective in imprving interfacial prperties f PC/SAN blend when AN cntent f SAN in blck cplymer was the same with that f SAN used in PC/ SAN blend. Based n the knwledge related t the miscibility f PMMA with SAN (r PC), cmmercially available PMMA was als examined as cmpatibilizer f PC/ ASA blend. Nte that PMMA is miscible with SAN cntaining AN frm 8 wt% t 33 wt% (Fwler et al., 1987; Suess et al., 1987) and PMMA blend with PC appeared t be right n the edge f miscibility (Kim et al., 1999; Kim and Paul, 1992). If cmmercially available plymers culd be used as a cmpatibilizer, it culd be an effective strategy fr cmmercial success f blend. 2. Materials and prcedure Plymers used in the experiments and their pertinent infrmatin were listed in Tables 1. PC, ASA (ASA-1, ASA-2, ASA-3, and ASA-4), SAN, and PMMA were prvided by LG Chemicals. TMPC-b-SAN cplymers were synthesized in this labratry. The detail prcedure fr the synthesis f TMPC-b-SAN was described elsewhere (Kang et al., 2000; Matsumt and Kanayama, 1988). PC/ SAN blends (r PC/ASA blends) were prepared by melt mixing. PC and SAN (r PC and ASA) were mixed in a trque rhemeter (Haake Rhemix) fr 15 min. at 60 rev/ min and 240 C. Blends f PC and ASA were als prepared by melt mixing in a twin extruder at 240 C. Interfacial tensin between PC and SAN, r that between PC and SAN cntaining varius amunt f cmpatibilizer, was measured with an imbedded-fiber retractin (IFR) technique (Carriere et al., 1989; Carriere and Chen, 1991; Chen and Carriere, 1989; Ellingsn et al., 1994). Fibers f PC cntaining varius amunts f cmpatibilizer were prduced with an Instrn fiber spinning apparatus. SAN cplymer sheets f 0.15 mm thickness cntaining cmpatibilzer were als prepared by cmpressin mlding at 220 C. PC fibers and SAN plates were dried under vacuum at 170 C and 110 C, respectively, fr 24 hurs t ensure that n elastic effects related t the fiber rientatin ccurred. PC fibers were then placed between tw sheets f SAN cplymer. The samples were subsequently transferred t a micrscpe equipped with a ht stage and a temperature cntrller. The samples were annealed at 180 C fr 2 hurs prir t bserving the fiber retractin prcess with an image analyzer at 240 C. Nte that PC fiber and SAN plate cntained the same amunt f cmpatibilizer. The zer shear viscsities (h) f PC and SAN cplymer were measured by using a Rhemetrics dynamic spectrmeter (RDS-II, Rhemetrics Inc.) ver the shear rate range frm 10 1 t 10 3 rads 1 under a nitrgen atmsphere at 240 C. Values fr h btained frm the lwfrequency plateau viscsities are listed in Table 1. The mechanical and thermal prperties f PC/ASA blends were measured accrding t the ASTM (American standard testing methd). T examine weld-line strength f blends, specimens having the same shape with the tensile test bar and cntaining weld-line at the center f sample bar were prepared by injecting mlding (See Fig.. Ten- Fig. 1. Specimen fr the test f weld-line strength. Table 1. Plymers used in this study Plymer Cplymer 1 Rubber ) 1 ) Zer shear cmpsitin M w M w M n cntent viscsity (pa s) Surces PC - 32, ,990 LG Chemicals (200-15) ASA-1 24% AN wt% - LG Chemicals (ASA 919) ASA-2 24% AN wt% - LG Chemicals (ASA 927) ASA-3 24% AN wt% - LG Chemicals (ASA 925) ASA-4 24% AN wt% LG Chemicals (ASA 929) SAN 24 24% AN 174, LG Chemicals (SAN 80HF) PMMA - 103, LG Chemicals (HI 830) TMPC-b-SAN 2) - 108, synthesized Infrmatin was prvided by supplier. 2) f TMPC = 42,000 M w 2 Krea-Australia Rhelgy Jurnal

3 PC/ASA blends having enhanced interfacial and mechanical prperties sile strength f these sample bars was defined as weld-line strength. Dynamic mechanical prperties such as strage mdulus and lss mdulus (r tan δ) were measured with Dynamic Mechanical Testing Apparatus (DMTA, Plymer Lab.). Blend mrphlgy was bserved with scanning electrn micrscpe (SEM, mdel: JEOL, JSM-840A) and transmissin electrn micrscpe (TEM, mdel: JEOL, JEM-2000EX II). T btain image cntrast fr SEM bservatin PC rich-phase in the blend samples were etched ut by immersing in an aqueus slutin cntaining 30 wt% NaOH. Samples were stained with RuO 4 and then micrtmmed fr TEM bservatin. 3. Results and discussin Fig. 2. Effects f cmpatibilizer cntent n the interfacial tensin between PC and SAN 24 cplymer. Nte that PC fiber and SAN 24 sheet cntained the same amunts f cmpatibilizer. Fig. 3. Weld-line strength f PC/ASA = 6/4 blends as a functin f cmpatibilizer cntent Cmpatibilizatin f blend and its weld-line strength Since acrylic rubber particles in ASA enclsed with grafted SAN n rubber particle r free SAN, PC frmed interface with SAN matrix f ASA. It is well recgnized that the interactins between PC and SAN cplymers cntaining varius amunts f AN are nt favrable enugh t prduce cmplete miscibility, althugh the evidence fr varying extents f miscibility has been reprted (Callaghan et al., 1993; Cheng et al., 1992; Guest and Daly, 1989; Keitz et al., 1984; Quentens et al., 199. Amng the varius PC/SAN blends, it was als knwn that PC blend with SAN cntaining abut 24 wt% AN (SAN 24) shwed ptimum interfacial adhesin regardless f blend cmpsitins. Because f this, the experiments reprted hereafter were perfrmed SAN 24. The interfacial tensin between PC and SAN 24 as a functin f the TMPC-b-SAN cntent (r PMMA cntent) was als measured by the imbedded fiber retractin (IFR) technique that was develped as a dynamic methd fr measuring the interfacial tensin between mlten, high mlecular weight plymers (Carriere et al., 1989; Carriere and Chen, 1991; Chen and Carriere, 1989; Ellingsn et al., 1994). The changes in the interfacial tensin f PC/ SAN 24 blend as a functin f the cmpatibilizer cntent were given in Fig. 2. The interfacial tensin decreased very rapidly fr cmpatibilizer cntent ranging frm 0 t 5 phr (parts per hundred resin) and then leveled ff. As exhibited in Fig. 2, bth cmpatibilzers, i.e., TMPC-b-SAN and PMMA, were effective in reducing interfacial tensin between PC and SAN even thugh TMPC-b-SAN was mre effective than PMMA. When tw cld-frnts meet during injectin mlding prcess, weld-line is frmed. Since the prduct frmed by the injectin mlding exhibited pr mechanical strength at arund weld-line, enhancement f mechanical strength at weld-line is an imprtant issue fr the applicatin f immiscible blend. Specimens shwn in Fig. 1 were prepared by injectin mlding t examine the effects f cmpatibilizer n the weld-line strength f PC/ASA blend. Weld-line was frmed at the center f tensile test bar by injecting plymer melt at the bth ends. Tensile strength examined with specimen shwn in Fig. 1 was defined as weld-line strength. Fig. 3 exhibited weld-line strength f PC/ASA-2 = 6/4 blends cntaining varius amunts f cmpatibilizer. The weld-line strength f blend cntinuusly increased with increase f cmpatibilizer cntent up t 5 phr and then leveled ff at a fixed value. Because f this, the experimental results reprted hereafter were thse Krea-Australia Rhelgy Jurnal March 2006 Vl. 18, N. 1 3

4 M. S. Kang, C. K. Kim and J. W. Lee Table 2. Mechanical and thermal prperties f PC/ASA =6/4 blends with r withut cmpatibilizer Prperties Test methd Tensile strength (MPa) Tensile elngatin (%) Flexural strength (MPa) ASTM D790 Flexural mdulus (MPa) ASTM D790 ASTM D256 Izd impact strength (25 C, J/m) ASTM D256 Izd impact strength ( 10 C, J/m) ASTM D648 HDT (1/4, 265 kg/cm, C) Weld-line strength (MPa) cmpatibilizer cntent f blends: 5 phr. 2 PC/ASA PC/ASA-2/TMPC-b-SAN PC/ASA-2/PMMA fr blends cntaining 5 phr cmpatibilizer. As listed in Table 2, blends (PC/ASA-2=6/4) exhibited similar mechanical and thermal prperties whether blends cntained cmpatibilizer r nt. Hwever, blends exhibited huge difference in weldline strength. Weld-line strength f blend crrespnded t abut 35% f its tensile strength when blend did nt cntain cmpatibilzer. Hwever, weld-line strength f blend recvered up t 85% f its tensile strength when blend cntains 5 phr TMPC-b-SAN as cmpatibilizer. The result related t weld-line strength indicated that bth f TMPCb-SAN and PMMA culd be used as excellent cmpatibilizer fr PC/ASA blends, even thugh the frmer was better than the latter as exhibited in Fig. 3. Crss sectinal mrphlgy f weld-line was bserved with SEM. In here, PC rich-phase was etched ut with 30 wt% NaOH aqueus slutin. As shwn in Fig. 4, changes in mrphlgy als cnfirmed that cmpatibility f PC/ASA blend culd be enhanced by adding prper cmpatibilizer Mechanical prperties f PC/ASA blends Fur different types f ASA terplymers were blended with PC. Average diameter f the rubber particles in ASA1 and ASA-2 was the same (0.4 µm), while rubber particles in ASA-1 cntained SAN within the rubber phase. Rubber particles in ASA-3 (average diameter f rubber particles: 0.1 µm) and thse in ASA-4 (average diameter f rubber particles: 0.6 µm) did nt cntain SAN within the rubber phase. Blends cntaining 60 wt% f PC, 40 wt% f ASA, and 5 phr f TMPC-b-SAN (r PMMA) as cmpatibilizer were prepared and then their mechanical and thermal prperties were examined. As listed in Table 3, blends exhibited similar mechanical prperties except the impact strength. At arund rm temperature, impact strength f blends cntaining ASA-3 (r ASA-4) lwer than that f ther blends cntaining ASA-1 (r ASA-2). Blends cntaining ASA-1 (r ASA-2) exhibited similar impact strength at arund rm temperature. It means that impact strength f blends at arund rm temperature was affected by rubber particle size, while it did nt depend n 4 Fig. 4. Crss sectinal mrphlgies at weld-line; (a) blend des nt cntain cmpatibilizer; (b) blend cntains 5 phr TMPC-b-SAN cplymer as cmpatibilizer. whether SAN was included within rubber particles r nt. Impact strength f blend at lw temperature an imprtant issue fr the autmbile applicatin. Blend cntaining ASA-2 exhibited higher impact strength at lw temperature ( 10C) than that cntaining ASA-1, even thugh these blends exhibited similar impact strength at arund rm Krea-Australia Rhelgy Jurnal

5 PC/ASA blends having enhanced interfacial and mechanical prperties Table 3. Mechanical and thermal prperties f PC/ASA blends Prperties Test methd Tensile strength (MPa) Tensile elngatin (%) Flexural strength (MPa) ASTM D790 Flexural mdulus (MPa) ASTM D790 Izd impact strength (25 C, J/m) ASTM D256 Izd impact strength ( 10 C, J/m) ASTM D256 ASTM D648 HDT (1/4, 265 kg/cm, C) Blends cntain 60 wt% PC, 40 wt% ASA, and 2 PC/ASA-1/ PC/ASA-2/ TMPC-b-SAN TMPC-b-SAN phr cmpatibilizer. PC/ASA-2/ PC/ASA-3/ PC/ASA-4/ PMMA TMPC-b-SAN TMPC-b-SAN , Fig. 5. Dynamic mechanical behavir (tan d) f PC/ASA-1 and PC/ASA-2 blends. temperature. T understand the difference in the impact strength at lw temperature, glass transitin temperatures (Tg) f blend were examined with DMTA. Fig. 5 exhibited tan δ f blends cntaining ASA-1 and ASA-2. Tg f acrylic elastmer in ASA-1 was 17C while that f acrylic elastmer in ASA-2 was 34C. Nte that Tg f plybutylacrylate is abut 40C. Tg shift f rubber phase in ASA2 might cme frm grafted SAN n the rubber particle, while that f ASA-1 might cme frm grafted SAN as well as SAN included within rubber particles. The Tg shift f the rubber phase t the high temperature resulted in pr impact strength at lw temperature. These results indicated that PC/ASA blend having ptimum impact strength might be prduced when average diameter f rubber particles that d nt cntained SAN within rubber phase is abut 0.4 µm Changes in blend mrphlgy with cmpatibilizer The effects f cmpatibilizer n the mrphlgy f the blend (PC/ASA = 6/4) were explred with SEM and TEM. Krea-Australia Rhelgy Jurnal Fig. 6. Crss sectinal mrphlgies f blends; (a) blend des nt cntain cmpatibilizer; (b) blend cntains 5 phr PMMA cplymer as cmpatibilizer. Samples were prepared by melt mixing and then cmpress mlded at 240C. Fig. 6 exhibited micrphtgraphs f blends with (Fig. 6-b) r withut (Fig. 6-a) cmpatibilizer. As shwn in Fig. 6, cmpatibility f blend was enhanced March 2006 Vl. 18, N. 1 5

M. S. Kang, C. K. Kim and J. W. Lee Fig. 8. Crss sectinal mrphlgies f blends btained at tw Fig. 7. Crss sectinal mrphlgies f blends cntaining 5 phr TMPC-b-SAN; (a) PC/ASA-2 blend; (b) PC/ASA-3 blend.

4 by adding TMPC-bSAN as cmpatibilizer. Fig. 7 exhibited blend mrphlgy bserved with TEM by staining rubber phase and PC-rich phase with RuO4.

6 M. S. Kang, C. K. Kim and J. W. Lee Fig. 8. Crss sectinal mrphlgies f blends btained at tw Fig. 7. Crss sectinal mrphlgies f blends cntaining 5 phr TMPC-b-SAN; (a) PC/ASA-2 blend; (b) PC/ASA-3 blend. Nte that image cntrast was btained with RuO staining. different sampling psitins 1 and 2 when blend cntains TMPC-b-SAN cplymer as cmpatibilizer; (8-a): psitin 1, (8-b). 4 by adding TMPC-bSAN as cmpatibilizer. Fig. 7 exhibited blend mrphlgy bserved with TEM by staining rubber phase and PC-rich phase with RuO4. Since staining speed f SAN-rich phase (bright), PC-rich phase (slightly dark), and rubber phase (dark) is different, cntrast amng these three phases was btained with RuO4 staining (Cheng et al., 1992). As shwn in Fig. 7, when blends cntained TMPC-b-SAN as cmpatibilizer, SAN rich-phase was well dispersed in PC rich-phase and aggregated rubber particles included within SAN rich-phase. Mrphlgy f blend prepared by cmpressin mlding was similar regardless f the sampling psitin. Hwever, mrphlgy f blend prepared by injectin mlding depends n the psitin. Figs. 8 and 9 exhibited crss sectinal mrphlgies f tensile bar (center f crss sectin) 6 at tw different psitins, 1 and 2 in Figs. 8 and 9. Cmpatibility f blend cntaining PMMA (r TMPC-b-SAN) as cmpatibilizer decreased with the distance frm the gate. Even thugh changes in the mrphlgy f blend cntaining TMPC-b-SAN cplymer was als bserved (Fig. 8), dimensinal stability f blend cntaining TMPCb-SAN was better than that f blend cntaining PMMA (Fig. 9). Cmpatibilizer added t blend nt nly reduced the interfacial tensin but als intrduced a steric stabilizatin f the dispersed phase (Paul et al., 1988). The mre effective cmpatibilizer was used, the mre stable dispersed phase is frmed. Blend cntaining TMPC-bSAN as cmpatibilizer exhibits better dimensinal stability than that cntaining PMMA as cmpatibilizer. Even thugh PC/ASA blend cntaining TMPC-b-SAN as cmpatibilizer exhibited better interfacial prperties than that Krea-Australia Rhelgy Jurnal

7 PC/ASA blends having enhanced interfacial and mechanical prperties PC/ASA blend even thugh TMPC-b-SAN was mre effective than PMMA. Weld-line strength f blend cntaining TMPC-b-SAN cplymer reached up t 85% f its tensile strength, while weld-line strength f blend that did nt cntain cmpatibilzer was 35% f its tensile strength. Except impact strength, mechanical prperties f PC/ASA blends examined here were similar regardless f rubber particle size and shape. PC/ASA blend exhibited ptimum impact strength when average diameter f rubber particles that d nt cntain SAN within rubber phase is abut 0.4 µm. Acknwledgement This study was supprted by research grants frm the Krea Science and Engineering Fundatin (KOSEF) thrugh the Applied Rhelgy Center (ARC), an fficial KOSEF-created engineering research center (ERC) at Krea University, Seul, Krea. References Fig. 9. Crss sectinal mrphlgies f blends btained at tw different sampling psitins 1 and 2 when blend cntains PMMA as cmpatibilizer: (9-a): psitin 1, (9-b): psitin 2. cntaining PMMA as cmpatibilizer, experimental results cnfirmed that cmmercially available PMMA culd be als used as a prmising cmpatibilizer f PC/ASA blend. As cnclusin, PC/ASA blend that satisfied required prperties fr the applicatin f autmtive parts such as autmtive grilles and exterirs culd be develped by adding prper cmpatibilizer as well as by cntrlling mrphlgy f acrylic elastmer and its size. 4. Summary Blend f PC and ASA having imprved mechanical prperties and weld-line strength was develped fr the autmbile applicatin. T enhance the interfacial adhesin between PC and SAN matrix f ASA, tw different types f cmpatibilizers, i.e., TMPC-b-SAN and PMMA were added t PC/ASA blend. Bth were effective in imprving interfacial prperties (r weld-line strength) f Krea-Australia Rhelgy Jurnal Callaghan, T.A., K. Takakuwa, D.R. Paul and A.R. Padwa, 1993, Plycarbnate-SAN Cplymer Interactin, Plymer 34, Carriere, C.J. and A.J. Chen, 1991, Evaluatin f the interfacial tensin between high mlecular weight plycarbnate and PMMA resins with the imbedded fiber retractin technique, J. Rhelgy 35, Carriere, C.J., A.J. Chen and C.B. Arends, 1989, Estimatin f interfacial tensin using shape evlutin f shrt fiber, J. Rhelgy 33(5), Cheng, T.W., H. Keskkula and D.R. Paul, 1992, Prperty and mrphlgy relatinships fr ternary blends f plycarbnate, brittle plymers and an impact mdifier, Plymer 33, Chen, A.J. and C.J. Carriere, 1989, Analysis f a retractin mechanism fr imbedded plymeric fibers, Rhel. Acta 28, Ellingsn, P.C., D.A. Strand, A. Chen, R.L. Sammler and C.J. Carriere, 1994, Mlecular weight dependence f PS/PMMA interfacial tensin by embedded-fiber retractin, Macrmlecules 27, Fwler, M.E., H. Keskkula and D.R. Paul, 1987, Miscibility and their phase behavir f PMMA and SAN blends, Plymer 28, Freitag, D., U. Grig, P.R. Muller and W. Nuvertne, 1988, Plycarbnates, in Encyclpedia f Plymer Science and Engineering (Eds Mark, H.F., N.M. Bikales, C.G. Overberger and G. Menges) 2 edn. Jhn Wiley, New Yrk, 11, 648. Guest, M. and J.H. Daly, 1989, The use f glass transitin data fr characterizatin plycarbnate-based blends, Eur. Plym. J. 25(9), Kang, E.A., J.H. Kim, C.K. Kim, H.W. Rhee and S.Y. Oh, 2000, The effects f PC-PMMA diblck cplymer n the cmpatability and interfacial prperties f PC/PMMA blends, March 2006 Vl. 18, N. 1 nd 7

8 M. S. Kang, C. K. Kim and J. W. Lee Plym. Eng. Sci. 40, Keitz, J.D., J.W. Barlw and D.R. Paul, 1984, Plycarbnate blends with styrene/acrylnitrile cplymers, J. Appl. Plym. Sci. 29, Kim, C.K. and D.R. Paul, 1992, Interactin parameters fr blend cntaining plycarbnats : 3. cplycarbnates and styrenebased cplymers, Plymer 33, Kim, J.H., M.J. Kim, C.K. Kim and J.W. Lee, 2001, Cntrl f mrphlgy and interfacial tensin f PC/SAN blends with cmpatibilizer, Krea-Australia Rhelgy Jurnal 13(3), Kim, M.H., J.H. Kim, C.K. Kim, Y.S. Kang and H.C. Park, 1999, Cntrl f phase separatin behavir f PC/PMMA blends and their applicatin t the gas separatin, J. Plym. Sci: Part B 37, Matsumt, T. and S. Kanayama, 1988, Preparatin f PC-b-PS cplymer and their applicatins, JP Pat Paul, D.R., J.W. Barlw and H. Keskkula, 1988, Plymer blend, in Encyclpedia f Plymer Science and Engineering (Eds Mark, H. F., N. M. Bikales, C. G. Overberger and G. Menges) 2 nd edn. Jhn Wiley, New Yrk, 12, Quentens, D., G. Greninckx, M. Guest and M. Aerts, 1991, Phase mrphlgy characterizatin and ultimate mechnical prperties f PC/SAN blend : Influence f the AN cntent f SAN, Plym. Eng. Sci. 31, Suess, M., J. Kresseler and H.W. Krammer, 1987, The miscibility windw f PMMA/SAN blends, Plymer 28, Wl, R.P., 1989, Plymer Interfaces, Structure and Strength, Hanser Publishers, 336. Wrks, G., 1996, Acrylnitrile-acrylic elastmer-styrene terplymer In: Jseph CS editr, Plymeric Materials Encyclpedia, CRC Press, New Yrk, 1, Krea-Australia Rhelgy Jurnal

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