{"id":99243,"date":"2020-10-29T14:57:52","date_gmt":"2020-10-29T06:57:52","guid":{"rendered":"https:\/\/www.alpapowder.com\/99243\/"},"modified":"2021-08-10T10:35:49","modified_gmt":"2021-08-10T02:35:49","slug":"ung-dung-cua-axit-stearic-trong-bien-tinh-be-mat-cua-canxi-cacbonat-nanomet","status":"publish","type":"post","link":"https:\/\/www.alpapowder.com\/vi\/99243\/","title":{"rendered":"\u1ee8ng d\u1ee5ng c\u1ee7a axit stearic trong bi\u1ebfn t\u00ednh b\u1ec1 m\u1eb7t c\u1ee7a canxi cacbonat nanomet"},"content":{"rendered":"
C\u00f3 hai khi\u1ebfm khuy\u1ebft ch\u00ednh trong vi\u1ec7c \u1ee9ng d\u1ee5ng nano canxi cacbonat v\u00e0o m\u00f4i tr\u01b0\u1eddng h\u1eefu c\u01a1: m\u1ed9t l\u00e0 nano canxi cacbonat l\u00e0 v\u1eadt li\u1ec7u v\u00f4 c\u01a1 c\u00f3 b\u1ec1 m\u1eb7t \u01b0a n\u01b0\u1edbc v\u00e0 k\u1ef5 n\u01b0\u1edbc. N\u00f3 c\u00f3 kh\u1ea3 n\u0103ng ph\u00e2n t\u00e1n k\u00e9m trong polyme v\u00e0 k\u00e9m \u00e1i l\u1ef1c v\u1edbi sinh v\u1eadt. D\u1ec5 h\u00ecnh th\u00e0nh c\u00e1c ch\u1ea5t k\u1ebft t\u1ee5 a, d\u1eabn \u0111\u1ebfn suy gi\u1ea3m t\u00ednh n\u0103ng c\u1ee7a v\u1eadt li\u1ec7u; Th\u1ee9 hai, nano canxi cacbonat c\u00f3 k\u00edch th\u01b0\u1edbc h\u1ea1t nh\u1ecf, s\u1ed1 l\u01b0\u1ee3ng nguy\u00ean t\u1eed b\u1ec1 m\u1eb7t l\u1edbn, n\u0103ng l\u01b0\u1ee3ng b\u1ec1 m\u1eb7t l\u1edbn, l\u1ef1c t\u01b0\u01a1ng t\u00e1c gi\u1eefa c\u00e1c h\u1ea1t m\u1ea1nh n\u00ean d\u1ec5 h\u00ecnh th\u00e0nh s\u1ef1 k\u1ebft t\u1ee5 c\u1ee7a b\u1ed9t nano canxi cacbonat. Khi l\u01b0\u1ee3ng nano canxi cacbonat \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng t\u0103ng l\u00ean, c\u00e1c khuy\u1ebft t\u1eadt n\u00e0y c\u00e0ng l\u1ed9 r\u00f5, vi\u1ec7c tr\u00e1m qu\u00e1 nhi\u1ec1u s\u1ebd khi\u1ebfn v\u1eadt li\u1ec7u kh\u00f4ng s\u1eed d\u1ee5ng \u0111\u01b0\u1ee3c.<\/p>\n
Axit stearic l\u00e0 m\u1ed9t axit b\u00e9o b\u00e3o h\u00f2a m\u1ea1ch cacbon d\u00e0i ph\u1ed5 bi\u1ebfn. N\u00f3 c\u00f3 c\u1ea3 ph\u1ea7n cu\u1ed1i \u01b0a b\u00e9o c\u1ee7a chu\u1ed7i cacbon d\u00e0i v\u00e0 ph\u1ea7n cu\u1ed1i \u01b0a n\u01b0\u1edbc c\u1ee7a nh\u00f3m cacboxyl. B\u1ec1 m\u1eb7t c\u1ee7a nano canxi cacbonat c\u00f3 t\u00ednh \u01b0a n\u01b0\u1edbc, v\u00ec v\u1eady axit stearic \u0111\u01b0\u1ee3c ph\u1ee7 tr\u00ean nano, b\u1ec1 m\u1eb7t c\u1ee7a canxi cacbonat c\u00f3 th\u1ec3 c\u1ea3i thi\u1ec7n \u0111\u00e1ng k\u1ec3 t\u00ednh \u01b0a b\u00e9o c\u1ee7a n\u00f3. Khi n\u00f3 \u0111\u01b0\u1ee3c l\u1ea5p \u0111\u1ea7y b\u1eb1ng cao su, ch\u1ea5t d\u1ebbo, m\u1ef1c in ti\u00ean ti\u1ebfn, di\u1ec7n t\u00edch b\u1ec1 m\u1eb7t ri\u00eang l\u1edbn v\u00e0 n\u0103ng l\u01b0\u1ee3ng b\u1ec1 m\u1eb7t ri\u00eang cao c\u00f3 l\u1ee3i cho m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c h\u1ea1t canxi cacbonat v\u00e0 c\u00e1c ph\u00e2n t\u1eed polyme h\u1eefu c\u01a1. S\u1ef1 li\u00ean k\u1ebft ch\u1eb7t ch\u1ebd gi\u1eefa ch\u00fang c\u00f3 th\u1ec3 l\u00e0m cho b\u1ec1 m\u1eb7t c\u1ee7a s\u1ea3n ph\u1ea9m s\u00e1ng v\u00e0 c\u00f3 hi\u1ec7u su\u1ea5t tuy\u1ec7t v\u1eddi.<\/p>\n
1. C\u01a1 ch\u1ebf c\u1ee7a l\u1edbp ph\u1ee7 axit stearic canxi cacbonat bi\u1ebfn t\u00ednh nanomet<\/p>\n
Trong nh\u1eefng n\u0103m g\u1ea7n \u0111\u00e2y, c\u00e1c nghi\u00ean c\u1ee9u v\u1ec1 l\u1edbp ph\u1ee7 v\u00e0 \u0111i\u1ec1u ch\u1ebf canxi cacbonat nanomet b\u1eb1ng axit stearic c\u0169ng \u0111\u00e3 xu\u1ea5t hi\u1ec7n kh\u00f4ng ng\u1eebng.<\/p>\n
Chen Yijian v\u00e0 c\u1ed9ng s\u1ef1. \u0111\u00e3 kh\u00e1m ph\u00e1 qu\u00e1 tr\u00ecnh h\u00ecnh th\u00e0nh c\u1ee7a tinh th\u1ec3 canxi cacbonat \u0111\u01a1n l\u1edbp axit stearic (SA) \u1edf m\u1eb7t ph\u00e2n c\u00e1ch kh\u00f4ng kh\u00ed v\u00e0 n\u01b0\u1edbc. S\u1eed d\u1ee5ng k\u00ednh hi\u1ec3n vi \u0111i\u1ec7n t\u1eed v\u00e0 k\u00ednh hi\u1ec3n vi g\u00f3c Brewster t\u1ea1i ch\u1ed7 \u0111\u1ec3 ki\u1ec3m tra v\u00e0 x\u00e1c \u0111\u1ecbnh \u0111\u1eb7c t\u00ednh, ng\u01b0\u1eddi ta \u0111\u00e3 quan s\u00e1t th\u1ea5y r\u1eb1ng d\u01b0\u1edbi l\u1edbp \u0111\u01a1n l\u1edbp c\u1ee7a axit stearic, c\u00e1c tinh th\u1ec3 canxi cacbonat cu\u1ed1i c\u00f9ng \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh b\u1edfi ti\u1ec1n ch\u1ea5t c\u1ee7a h\u1ea1t ch\u1ee9 kh\u00f4ng ph\u1ea3i b\u1eaft ngu\u1ed3n tr\u1ef1c ti\u1ebfp t\u1eeb qu\u00e1 tr\u00ecnh solvat h\u00f3a. ion. T\u1eeb k\u00ednh hi\u1ec3n vi \u0111i\u1ec7n t\u1eed qu\u00e9t (SEM) v\u00e0 k\u00ednh hi\u1ec3n vi \u0111i\u1ec7n t\u1eed truy\u1ec1n qua (TEM), c\u00f3 th\u1ec3 th\u1ea5y r\u1eb1ng c\u00e1c h\u1ea1t ti\u1ec1n ch\u1ea5t l\u00e0 nh\u1eefng h\u00ecnh c\u1ea7u \u0111\u1ed3ng nh\u1ea5t c\u1ee7a canxi cacbonat v\u00f4 \u0111\u1ecbnh h\u00ecnh c\u00f3 \u0111\u01b0\u1eddng k\u00ednh nh\u1ecf h\u01a1n 100 nm. Th\u00ed nghi\u1ec7m t\u1ea1o ra canxi cacbonat th\u00f4ng qua ph\u1ea3n \u1ee9ng c\u1ee7a Ca (OH) 2 v\u00e0 CO2. Canxi cacbonat v\u00f4 \u0111\u1ecbnh h\u00ecnh \u0111\u01b0\u1ee3c t\u1ea1o ra trong giai \u0111o\u1ea1n \u0111\u1ea7u c\u1ee7a qu\u00e1 tr\u00ecnh kho\u00e1ng h\u00f3a, v\u00e0 n\u00f3 t\u1ed3n t\u1ea1i \u1ed5n \u0111\u1ecbnh trong \u00edt nh\u1ea5t 0,5 gi\u1edd. Khi s\u1ed1 l\u01b0\u1ee3ng t\u0103ng l\u00ean, canxi cacbonat v\u00f4 \u0111\u1ecbnh h\u00ecnh k\u1ebft t\u1ee5 l\u1ea1i t\u1ea1o th\u00e0nh canxi cacbonat pha Canxit.<\/p>\n
<\/p>\n
Xuetao Shi v\u00e0 c\u1ed9ng s\u1ef1. \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng axit stearic th\u01b0\u01a1ng m\u1ea1i \u0111\u1ec3 ph\u1ee7 canxi cacbonat k\u1ebft t\u1ee7a trong \u0111i\u1ec1u ki\u1ec7n pha n\u01b0\u1edbc, h\u00e0m l\u01b0\u1ee3ng axit stearic trong canxi cacbonat ph\u1ee7 l\u00e0 3% \u0111\u1ebfn 13,5%. Ph\u00e2n t\u00edch h\u1ed3ng ngo\u1ea1i Fourier (FTIR), nhi\u1ec7t tr\u1ecdng l\u01b0\u1ee3ng (TG) v\u00e0 \u0111o nhi\u1ec7t l\u01b0\u1ee3ng qu\u00e9t vi sai (DSC) cho th\u1ea5y kh\u00f4ng c\u00f3 axit stearic t\u1ef1 do tr\u00ean b\u1ec1 m\u1eb7t c\u1ee7a canxi cacbonat, ch\u1ec9 c\u00f3 canxi stearat. Ng\u01b0\u1eddi ta th\u1ea5y r\u1eb1ng canxi stearat \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh \u0111\u01b0\u1ee3c h\u1ea5p ph\u1ee5 m\u1ed9t ph\u1ea7n v\u1ec1 m\u1eb7t h\u00f3a h\u1ecdc v\u00e0 m\u1ed9t ph\u1ea7n h\u1ea5p ph\u1ee5 v\u1ec1 m\u1eb7t v\u1eadt l\u00fd tr\u00ean b\u1ec1 m\u1eb7t c\u1ee7a l\u1edbp ph\u1ee7, v\u00e0 c\u00f3 th\u1ec3 gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 canxi cacbonat kh\u00f4ng th\u1ec3 ph\u1ee7 ho\u00e0n to\u00e0n tr\u00ean b\u1ec1 m\u1eb7t trong \u0111i\u1ec1u ki\u1ec7n pha n\u01b0\u1edbc. L\u01b0\u1ee3ng s\u01a1n ph\u1ee7 t\u1ed1i \u0111a l\u00e0 3,25%.<\/p>\n
2. \u1ea2nh h\u01b0\u1edfng c\u1ee7a axit b\u00e9o m\u1ea1ch d\u00e0i v\u1edbi canxi cacbonat<\/p>\n
C\u00e1c axit b\u00e9o chu\u1ed7i d\u00e0i c\u0169ng c\u00f3 \u1ea3nh h\u01b0\u1edfng quan tr\u1ecdng \u0111\u1ebfn s\u1ef1 h\u00ecnh th\u00e0nh canxi cacbonat.<\/p>\n
Jiuxin Jiang v\u00e0 c\u1ed9ng s\u1ef1. \u0111\u00e3 th\u00eam c\u00e1c axit b\u00e9o chu\u1ed7i d\u00e0i kh\u00e1c nhau-axit lauric (axit lauric), axit palmitic (axit hexadecanoic) v\u00e0 axit stearic (axit octadecanoic) trong khi th\u1ed5i kh\u00ed cacbonic v\u00e0o huy\u1ec1n ph\u00f9 canxi hydroxit. Axit) \u0111\u1ec3 kh\u00e1m ph\u00e1 s\u1ef1 h\u00ecnh th\u00e0nh canxi cacbonat. Ng\u01b0\u1eddi ta th\u1ea5y r\u1eb1ng vi\u1ec7c b\u1ed5 sung c\u00e1c axit b\u00e9o chu\u1ed7i d\u00e0i kh\u00f4ng \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn d\u1ea1ng tinh th\u1ec3 c\u1ee7a canxi cacbonat, nh\u01b0ng \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn h\u00ecnh th\u00e1i c\u1ee7a c\u00e1c h\u1ea1t canxi cacbonat \u0111\u01b0\u1ee3c t\u1ea1o ra. Khi axit lauric \u0111\u01b0\u1ee3c th\u00eam v\u00e0o, kh\u1ea3 n\u0103ng ph\u00e2n t\u00e1n c\u1ee7a c\u00e1c h\u1ea1t canxi cacbonat \u0111\u01b0\u1ee3c c\u1ea3i thi\u1ec7n \u0111\u00e1ng k\u1ec3; khi m\u1ed9t l\u01b0\u1ee3ng l\u1edbn axit palmitic v\u00e0 axit stearic \u0111\u01b0\u1ee3c th\u00eam v\u00e0o, c\u1ea5u tr\u00fac gi\u1ed1ng vi m\u00f4 v\u00e0 c\u1ea5u tr\u00fac gi\u1ed1ng tr\u1ee5c ch\u00ednh \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh. T\u00e1c gi\u1ea3 \u0111\u1ec1 xu\u1ea5t r\u1eb1ng trong qu\u00e1 tr\u00ecnh ph\u1ea3n \u1ee9ng cacbon h\u00f3a c\u1ee7a canxi hi\u0111roxit v\u00e0 cacbon \u0111ioxit, m\u1ed9t m\u1eb7t, \u0111\u1ed9 d\u00e0i c\u1ee7a chu\u1ed7i cacbon \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn h\u00ecnh d\u1ea1ng c\u1ee7a c\u00e1c mixen \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh b\u1edfi huy\u1ec1n ph\u00f9 canxi hi\u0111roxit, m\u1eb7t kh\u00e1c, ch\u1ebf \u0111\u1ed9 ti\u1ebfp x\u00fac gi\u1eefa c\u00e1c mixen x\u00e1c \u0111\u1ecbnh s\u1ef1 h\u00ecnh th\u00e0nh cu\u1ed1i c\u00f9ng. H\u00ecnh th\u00e1i c\u1ee7a canxi cacbonat.<\/p>\n
<\/p>\n