TAP CHl KHOA HOC VA CONG NGHE Tap 47, s6 6, 2009 Tr 69-75 NGHIEN CU'U DO B^N BU'C XA TU' NGOAI, NHIET AM CUA MOT SO MANG PHU TREN CO SCy NHI/A ACRYLIC I. NGHIEN CUU ANH HUb-NG CUA BAN CHAT HOA HOC O^N 00 B^N BUC XA TU NGOAI, NHIET AM CUA MOT S6 MANG PHU TREN CO Sd" NHUA ACRYLIC LE XUAN HIEN, NGUYEN THIEN VU'O'NG, NGUYEN THj VIET TRlfU 1. MODAU Nhua acrylic do co nhieu tinh nang qui (ben thai tiet, dp bam di'nh cao, trong suot ) nen ttr lau da dugc lira chgn cho cac irng dung ngoai trai. Vi ly do kinh te va kT thuat, cac loai nhua acrylic thuong pham thuong la cac san pham dong triing hgp giira monome acrylat, metacrylat voi nhau hoac vai styren hay cac monome khac. Ban chst va ham lugng cac hgp phan trong nhua acrylic co anh huang rat lan den kha nang o':;_ thai tiet va cac tinh chat khac ctia mang phLi[I-3]. Do do viec nghien ctru danh gia anh huang cua chting toi dg ben thai tiet se giup cho viec lira chpn giai phap nang cao tuoi thg ciing nhu pham vi trng dung ctia mang phti. Bang thtr nghiem tu nhien nguai ta co the danh gia dp ben thai tiet cua cac mang phti huu ca vai dp tin cay cao. Tuy nhien phuang phap nay thuong doi hoi thai gian thtr nghiem dai. Phuang phap thti' nghiem gia toe trong phong thi nghiem tuy khong mo phong mgt each day du toan bg cac yeu to tac dgng ctia tu nhien len mang phti nhung lai cho phep danh gia nhanh do ben trong nhung dieu kien xac dinh. Do vay, nguai ta thuang ket hgp thir nghiem gia toe vai thir nghiem tu nhien de nghien ctru quy luat, ca che suy giam ctia vat lieu polyme va du bao tuoi thg ciia chiing [4 - 10]. Bai bao nay trinh bay mgt so ket qua nghien cu'u anh huong ciia ban chat boa hpc den dp ben biic xa tii' ngoai, nhiet am cua mgt so mang phii tren ca sa nhua acrylic. 2. PHAN THlTC NGHIEM 2.1. Nguyen lieu va hoa chat •••)(ii , - Nhua acrylic: Da sti' dung 2 loai nhua nhiet deo va 2 loai nhua nhiet ran. -I- Nhua acrylic nhiet deo: Sir dung loai nhua acrylic LORIAC AC 330-50, dang dung djch 50%, san pham ctia Longriver (Dai Loan) va nhira acrylic PARLOID B-66, copolyme metyl metacrylat/ butyl metacrylat, a dang bgt, co nhiet do thuy tinh hoa 50°C, trgng lugng phan ttr 70.000, san pham ctia Rtrhm & Haas (My). + Nhua acrylic nhiet ran (thanh phan A): Sir dung loai nhua acrylic polyol AC 7310, dang dung djch 63%, ham lugng nhom hydroxyl 2,4% so vai goc nhua, san pham cua Cong ty hoa chat Alliance (Singapore) va nhua acrylic polyol HSU 1168, dang dung djch 65%o, ham lupng nhom hydroxyl 4,3% so vai goc nhua, san pham cua Cong ty cong nghiep nhua A & P (Dai Loan). 69 Tac nhan khau mach cho nhua acrylic nhiet ran (thanh phan B): Sti' dung loai polyisocyanat Desmodur N-75, dang dung djch 75%, ham lugng nhom NGO 16% - 17%o so vai goc nhua, san pham ctia hang Bayer (Dtrc). - Dung moi: Da str dung toluen, xylen, etyl axetat, butyl axetat loai P ctia Trung Qu6c. 2.2. Phuo'ng phap tao mau Cac miu nhua acrylic nhiet deo va nhiet rin (thanh phan A va B) dugc pha che thanh dung djch 40%. Ti le phoi trgn thanh phin A va B ctia cac mau nhua nhiet ran tinh theo ti le mol OH/NCO = 1/1. Cac dung djch nay dugc su' dung de tao mang tren be mat tam nhiia polypropylen, say trong tti hut chan khong a 25T den trgng lugng khong doi, sau do tach lay mang nhua. Da tao 4 loai mang phu, chieu day 15 pm: ACl : mang phu tren ca sa nhua AC 330-50; AC2 : mang phii tren ca sa nhua B-66; ACUl: mang phu tren ca sa nhua AC 7310 khau mach bang N-75; ACU2: mang phti tren ca sa nhua HSU 1168 khau mach bang N-75. 2.3. Phu-cng phap thir nghiem birc xa tir ngoai, nhiet am ' Thti' nghiem dp ben btrc xa ttr ngoai, nhiet am (BXTNNA) ctia cac mang phu dugc thuc hien tren thilt bj Atlas UVCON UC-327-2 theo tieu chuan ASTM D 4587-91, chl dp D (1 chu ki gom 8 gia chieu ttr ngoai a 60°C; 4 gia ngung nuoc a 45°C). Nguon bu'c xa tu ngoai la den huynh quang UVB-313, co buac song ?iniax = 313 nm, cuong dp bu'c xa irng vai X^ax la 0,8 W/m". 2.4. Phuong phap phan tich Bien doi cac nhom nguyen ttr (NT) ctia mang phu trong qua trinh thtr nghiem BXTNNA dugc xac djnh dua vao su thay doi mat dp quang D ctia hap thu dae trung cua chting tren pho hong ngoai bang thiet bj FT-IR, NEXUS 670, Nicole (My), tai Vien KT thuat nhiet doi, Vien KH & CN Viet Nam. Phan con lai (P) ctia cac nhom NT sau thai gian thtr nghiem 7 dugc tinh toan theo cong thu'c: P = (D,/Do) X 100% trong do: DQ, D? lan lugt la mat do quang ctia hap thu dae trung ctia nhom NT truac va sau thai gian thtr nghiem T. 3. KET QUA VA THAO LUAN 3.1 Bien doi hoa hoc trong mang phii diroi tac dung ciia BXTNNA 3.1.1. Nghien citv bien ddi cdc hdp thu dgc tnmg cho cdc nhdm NT tren phd hdng ngogi ciia cdc mdng phit trude vd sau khi thie nghiem BXTNNA 70 Ket qua nghien cii'u pho hong ngoai ciia cac mang phti ban dau va trong qua trinh thtr nghiem BXTNNA dugc trinh bay tren bang 1, 2 va hinh 1 cho thay trong qua trinh thii' nghiem, cac hap thu dae trung tai 2960-2935, 1525, 1385, 760, 700 cm"' co quy luat bien doi ro rang va khong bj anh htrong bai cac hap thu khac. Cac hap thu dae trung con lai bj xen phu va co quy luat bien doi khong ro rang. Do do, cac hap thu tai 2935, 1525, 1385 va 760 cm"' dugc lira chgn de nghien cii'u bien doi hoa hgc trong cac mang phti duai tac dung cua BXTNNA. Cac ket qua thu dugc cho phep nghien ciru mpt each djnh lupng bien doi hoa hpc ctia mang phii 3.1.2. Bien doi hod hoc trong cdc mdng phit duai tdc dung cua BXTNNA Ket qua phan tich bien doi ciia cac nhom NT trong cac mang phti ACl, AC2, ACUl va ACU2 dugc trinh bay trong bang 2. Co the thay trong qua trinh thtr nghiem, cac hap thu tai 2935, 1525, 1385, 760 cm"' dae trung cho cac nhom CH2, CNH, CH3, CeH, giam ro ret, trong do cac hap thu dae trung cho cac nhom CNH va CHT giam manh nhat. Sau 30 chu ki thtr nghiem, nhom CNH chi con 27,6%) trong mang phii ACUl, 3\,2% trong mang phu ACU2; nhom CH2 con 52% trong mang phii ACUl, 54,8% trong mang phii ACU2, 94,7%o trong mang phu AC2; nhom CH3 con 75,8%) trong mang phii ACUl, 76,1% trong mang phii ACU2, 99,3% trong mang phti AC2; nhom CeHs con 84,3%o trong mang phti ACUl. Trong mang phii ACl, cac nhom CH2, CH3, CsHj chi con 71,6%, 85,2% va 86,9% sau 12 chu ki thtr nghiem. Trong qua trinh thir nghiem, cac mang phii chju tac dpng dong thai ciia buc xa tir ngoai, dp am va nhiet dp. Btrc xa tii' ngoai gay ra su suy giam va phan huy quang cua mang polyme. Do am gay ra suy giam mang do phan trng thuy phan cac nhom djnh chtrc khong ben nucc tren mach polyme. Nhiet do tang thtic day ca hai qua t inh tren. Ham lugng ciia cac nhom CNH va mpt phiin nhom CH2 giam manh co the dugc giai thich do su pha va cac lien ket C-N, C-0 trong cac nhom amit, uretan va sir but nguyen tir hydro a cacbon a lien ke nhom amit duoi tac dung cua birc xa tir ngoai tao ra monoxit cacbon va etylen. Co' che suy giam cac nhom chirc nay tuong tu trong polyamit va polyuretan mach thang. Ham lugng ctia nhom CH3, phan nhom CH2 con lai va nhom C(,H5 giam do su phan huy quang ciia cac hgp phan acrylat va styren a mach nhanh va mach chinh [5, 11, 12]. Bdng I. Bien doi cac hap thu dae trung clio cac nhom NT tren pho hong ngoai ctia cac hgp phan trong mang phti truac va sau khi thir nghiem BXTNNA TT 01 02 03 04 05 06 So song (cm"') 3550^3200 3100-3000 2960 ' 2930 2870 2850 Dao dong dae trung VQ-H. N-H (ruou, amit, uretan) Vc-H (vong benzen) Vc-U(kdx) (CH3) Vc-H(kdx) (CH2) Vc-H(dx) (CH3) Vc-H(dx) (CH2) ACl a * * * * * b * * * * • * AC2 a * * • • b * * * * * ACUl a * * * * * * b * * * • * * ACUl a * * * * * b * * * * * Nhan ;;et vc cu'ong do va su' bien doi tb, xp ; thay doi y; giam m, xp; giam m; giam manh m. xp; giam m, xp; giam 71 08 09 10 11 12 13 14 15 16 17 1765;1730 1688 1638 i600;~1500 1525 -1470^ 1450 1385;1365 1354;1210 1250-^1000 1100 + 700 Vc=o (este, uretan, amit, axit va andehit) Vc=o (amit, xeton) Vc=o (amit) Vc=c (vong benzen) 5N-H (amit va uretan) 5c-H (CH2) ;5c-H(kdx) (CH- 3) Sc-H(dx) (CH3) Vc-N (amit. uretan) vc-o (rugu, ete, este, uretan) OC-H, N-H (con ISc), va 8c-H(nf) (vong benzen) * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * rm; thay doi m, xp; thay doi y, xp; giam manh y; giam m; giam rat manh km, xp; giam tb; giam m, xp; giam m, xp ; thay doi 5c-H(n0i"m,_cachap thu khac yeu; giam Chu thich: a: mang phu truac khi thtr nghiem BXTNNA; b: mang phu sau khi thir nghiem; *: co hip thu; v: dao dong hoa tri; 5: dao dong bien dang; dx: doi xung; kdx: khong d6i xirng; nf: ngoai mat phSng; m: manh; rm: rat manh; km: kha manh; tb: trung binh; y: y6u; xp: bj xen phu. Ngoai phan buy quang cac nhom uretan con bj thuy phan. Qua trinh nay ciing lam giam them ham lugng nhom CNH tren mach polyme noi rieng va trong mang phu noi chung. Co the do la ly do lam nhom CNH giam manh ban so vai cac nhom khac. Quan sat pho hong ngoai ctia cac mang phti ban dau va trong qua trinh thtr nghiem co the nhan thay quy luat bien doi ctia cac hap thu tai 3380, 1730 cm"' dae trung cho cac nhom NH, OH, 0=0 khong ro rang. Dieu nay dugc giai thich ngoai qua trinh suy giam quang boa cac nhom amit bac hai, uretan, este acrylat von co trong mang phu lam giam cuang do cac hap thu dae trung cho chting a 3380, 1730 cm"' con co qua trinh tao thanh cac san pham oxy boa quang (amin bac mgt, hydroxyl, axit, andehyt, xeton) lam tang cuong do trong qua trinh thtr nghiem BXTNNA. Nhirng dieu nhan thay la ket qua ctia hai qua trinh canh tranh nay. Bdng 2. Ham lugng cac nhom NT {%) con lai trong mang phu trong qua trinh thtr nghiem BXTNNA Nhom NT CH2 Mang phu ACl AC2 ACUl ACU2 Thai gian thtr nghiem (chu ki) 6 82,2 99,5 83,9 89,3 12 71,6 98,2 72,7 77,8 24 - 96,2 56,3 59,4 30 - 94,7 52,0 54,8 36 - 93,7 - 51,6 48 - 91,4 - 72 CH3 CNH CiHs ACl AC2 ACUl ACU2 ACUl ACU2 ACl ACUl 98,4 99,7 88,1 93,9 72,0 85,2 94,7 99,0 85,2 99,5 82,2 84,0 52,9 64,7 86,9 95,0 - 99,4 76,4 77,7 33,3 39,6 - 88,7 - 99,3 75,8 76,1 27,6 31,2 - 84,3 - 99,1 - 76,0 - 25,4 - - - 99,0 - - - - - - 3.2. Anh hiro'ng cua ban chat hoa hoc cac mang phu den do ben BXTNNA Cac ket qua nghien cuu bien doi hoa hpc ctia mang phu trong qua trinh thii' nghiem BXTNNA bang pho hong ngoai cho thay ban chat hoa hpc ctia mang anh huong ro ret den do ben BXTNNA ctia chting. Bien doi ciia nhom CNH (%) n r 0 10 20 30 Thai gian thu nghiem (chu ki) 40 Bien doi ciia nhom CH2 (%) 100 80 60 40 - 20 - 0 0 b) 10 20 30 40 50 Bien doi ciia nhom CH3 (%) Bien doi ciia nhom CtHs (%) Tho'i gian thir nghiem (chu ki) 100 80 60 - 40 - 20 0 d) \ 1 1 1 0 10 20 30 40 Thdi gian thir nghiem (chu ki) Hinh I. Anh hucmg cua ban chat hoa hoc cua cac mang phii den bien doi ciia cac nhom NT trong mang phii (A)ACl, (•)AC2, (•)ACU1 , (•)ACU2 73 Hinh 1 trinh bay anh huong ciia ban chat hoa hpc cac mang ACl, AC2, ACUl, ACU2 den biln doi ctia cac nhom NT trong mang phti. Bang 2 va hinh 1 cho thay trong qua trinh thti' nghiem BXTNNA, ham lugng nhom CNH con lai trong mang phti ACU2 nhieu ban trong mang phti ACUl; ham lugng nhom C6H5 con lai trong mang phti ACUl nhieu hon trong mang phu ACl; ham lugng nhom CH? va CH3 con lai trong mang phii AC2 nhieu han nhieu trong mang phti ACU2, ACUl va ACl. Sau 48 chu ki thii' nhiem, ham lugng nhom CH? va CH3 trong mang phu AC2 con 91,4%) va 99%). Sau 48 chu ki thti' nghiem, pho hong ngoai ciia mang phu AC2 bien doi rat It so voi ban dau, mang vin chua bj hong. Bang mat thuang co the thay mang phii ACU2 bj rach sau 36 chu ki; Mang phu ACUl bj vang sau 24 chu ki va bj rach sau 30 chu ki; Mang phti ACl bj vang sau 6 chu ki va bj rach sau 12 chu ki thtr nghiem BXTNNA. Nhu vay, do ben BXTNNA ctia cac mang phii co the sap xep theo thu tu nhu sau: AC2 » ACU2 > ACUl » ACl. Dieu nay co the giai thich do su khac nhau ve thanh phan, cau trtic ctia cac chat tao mang. Trong phan tu' chat tao mang, cac lien ket C-H a vj trf a so vai vong benzen khong ben duoi tac dung ciia tia tir ngoai, trong khi do cac nhom uretan va amit khong ben am, khong ben nuac. Nhiet do tang trong qua trinh thtr nghiem lam tang ca hai qua trinh tren. Mang phii AC2 tren ca sa copolyme metyl metacrylat/ butyl metacrylat khong co cac nhom nguyen tu' neu tren nen rat ben BXTNNA. Mang phti ACU2 va ACUl co cac nhom uretan nen kem ben thai tiet ban; Mang phti ACUl c6 chtra goc styren nhay cam voi bu'c xa tir ngoai nen kem ben hon mang phii ACU2. Mang phii ACl rat kem ben BXTNNA so voi mang phii ACUl co the do AC 1 CO chu'a ham lugng goc styren cao hon. Thuc te thtr nghiem cho thay mang phii ACl khong ben BXTNNA, bj vang ngay sau 6 chu ki thu' nghiem va bj hong sau 12 chu ki thir nghiem BXTNNA. Mang phti AC2 rat ben BXTNNA, bj suy giam khong nhieu sau 48 chu ki thii' nghiem. Su suy giam ctia cac mang phii ACUl va ACU2 chti yeu do su bien doi boa hpc ciia cac nhom nguyen tu CNH va CH2. 4. KET LUAN Qua nghien ctru bien doi cac nhom nguyen tir trong mang phu tren co' sa nhua acrylic loai ACl, AC2, ACUl va ACU2 duoi tac dung ciia BXTNNA bang pho hong ngoai da chpn dugc cac hap thu tai 293 j, 1525, 1385 va 760 cm"' dae trung cho nhom CH,, CNH, CH3 va CaHj dung de nghien ciiu suy giam cac mang phti. Dp ben BXTNNA ctia cac mang phti giam theo thu' tu AC2 » ACU2 > ACU1 > AC 1. Lcyi cam an. Tap the tac gia chan thanh cam cyn Chuang trinh nghien cu-u 00 ban trong Unh vuc Khoa hgc Tu nhien da ho trg kinh phi 6e hoan thanh cong trinh nay. TAI LIEU THAM KHAO 1. Erich Penzel, BASF Aktiengesellschaft, Ludwigshfen - Polyacrylates, Industrial polymers Handbook 1 (2001)588-618. 2. Manfred Stickler, Rtihm GmbH, Darmstadt - Polymetacrylates, Industrial polymers Handbook 2(2001)619-642. 3. Benjamin B. Kine, Ronald W. Novak - Acrylic and metacrylic polymers. Encyclopedia of polymer science and engneering 1 (1985) 234-299. 74 4. Vti Dinh Cu - Co' sa KT thuat nhiet dai, Nha xuat ban van hoa thong tin. Ha Npi, 2003. 5. C. Deker - Effect of UV Radiation on PoKmcrs, Handbook of polymer Science and Technology 3 (1989) 541-604. 6. Warren D. Ketola and Douglas Grossman - Accelerated and Outdoor Durability Testing of Organic Materials, ASTM, U.S.A. 1994. 7. Le Xuan Hien, Nguyen Thj Viet Trieu, Nguyen Thien Vuang - Tap chi Hoa hpc 36 (3) (1998)36-39. 8. To Xuan Hang, Vii Ke Oanh, Trjnh Anh Tnic - Tap chi Khoa hpc va Cong nghe 41 (5) (2003)29-34. 9. Thai Hoang, Vu Minh Dii'c, Do Van Cong, Hoang Thj Trang - Tap chi khoa hgc va Cong nghe 42 (5) (2004) 44-50. 10. D6 Quang Khang, H6 Uy Liem - Tap chi Hoa hpc 36 (1)(1998) 51 -54. 11. B. Ranby, J. F. Rabek - Photodegradation, Photo-oxidation and Photostabilization of Polymers, Wiley, London, 1975. 12. G. Geuskens - Degradation and Stabilization of Polymers, Applied Science Publishers, Barking, Essex, England, 1975. SUMMARY STUDY OF THE HUMID HEAT, ULTRAVIOLET RADIATION DURABILITY OF SOME COATINGS BASED ON ACRYLIC RESINS I. STUDY OF THE INFLUENCE OF THE CHEMICAL NATURE ON THE HUMID HEAT, ULTRAVIOLET RADIATION DURABILITY OF SOME COATINGS BASED ON ACRYLIC RESINS The degradation of some coatings based on LORIAC acrylic resin AC 330-50, PARLOID acrylic resin B-66 and acrylic polyol AC 7310, HSU 1168 crosslinked by polyisocyanate Desmodur N-75 under the influence of ultraviolet radiation, humid heat have been studied. The obvious decrease of the CNH, CH2, CH3, CtHs groups and the formation of the products of the photo-oxidation (the primary amine, hydroxyl, acid, ceton) during the testing process have been proved by IR spectroscopic analysis. The humid heat, ultraviolet radiation durability of the coatings have been evaluated. Dia chi: Nhgn bdi ngdy 12 thdng 9 ndm 2008 Vien Ky thuat nhiet doi, VAST. 75 . Nhua acrylic nhiet deo: Sir dung loai nhua acrylic LORIAC AC 330-50, dang dung djch 50%, san pham ctia Longriver (Dai Loan) va nhira acrylic. The degradation of some coatings based on LORIAC acrylic resin AC 330-50, PARLOID acrylic resin B-66 and acrylic polyol AC 7310, HSU 1168 crosslinked