%0 Journal Article %1 STOKKE1991a %A STOKKE, B. T. %A KNUDSEN, K. D. %A SMIDSROD, O. %A ELGSAETER, A. %C 605 THIRD AVE, NEW YORK, NY 10158-0012 %D 1991 %I JOHN WILEY & SONS INC %J J. Appl. Polym. Sci. %K ;; [ISI:] conformation; electron-microscopy; polysaccharide; thermal-stability; transition %N 7 %P 2063 -- 2071 %T OPTICAL-ROTATION OF DILUTE AQUEOUS XANTHAN SOLUTIONS AT ELEVATED HYDROSTATIC-PRESSURE %V 42 %X The optical rotation of dilute aqueous xanthan solutions of ultrasonically depolymerized xanthan have been measured in the pressure range from 0.1 to 50 MPa. This was achieved using a high-pressure cell in a spectropolarimeter of original design. The conformational melting temperature T(m) of xanthan was found to decrease with increasing pressure. The pressure coefficients of the melting temperature at constant ionic strengths, I, was found to be (DELTA-T(m)/DELTA-p)I = -(9.5 +/- 4.0) 10(-8) K Pa-1 and (DELTA-T(m)/DELTA-p)I = -(20 +/- 10) 10(-8) K Pa-1 for solution ionic strengths of 10 mM NaCl and 25 mM NaCl, respectively. The largest shift in T(m) of xanthan for an increase in hydrostatic pressure pressure from 0.1 to 50 MPa is less than -10 K. The observed decrease in conformational transition temperature can have significant implications when xanthan is used in polymer or micellar flooding processes in high-salinity, high-temperature oil reservoirs where the reservoir temperature is close to the structural transition temperature at ambient pressure.

@article{STOKKE1991a, __markedentry = {[phpts:6]}, abstract = {The optical rotation of dilute aqueous xanthan solutions of ultrasonically depolymerized xanthan have been measured in the pressure range from 0.1 to 50 MPa. This was achieved using a high-pressure cell in a spectropolarimeter of original design. The conformational melting temperature T(m) of xanthan was found to decrease with increasing pressure. The pressure coefficients of the melting temperature at constant ionic strengths, I, was found to be (DELTA-T(m)/DELTA-p)I = -(9.5 +/- 4.0) 10(-8) K Pa-1 and (DELTA-T(m)/DELTA-p)I = -(20 +/- 10) 10(-8) K Pa-1 for solution ionic strengths of 10 mM NaCl and 25 mM NaCl, respectively. The largest shift in T(m) of xanthan for an increase in hydrostatic pressure pressure from 0.1 to 50 MPa is less than -10 K. The observed decrease in conformational transition temperature can have significant implications when xanthan is used in polymer or micellar flooding processes in high-salinity, high-temperature oil reservoirs where the reservoir temperature is close to the structural transition temperature at ambient pressure.}, added-at = {2011-11-04T13:47:04.000+0100}, address = {605 THIRD AVE, NEW YORK, NY 10158-0012}, author = {STOKKE, B. T. and KNUDSEN, K. D. and SMIDSROD, O. and ELGSAETER, A.}, biburl = {https://www.bibsonomy.org/bibtex/2cb1e7f8fa4e427e3ffdd58be6ec84ae6/pawelsikorski}, citedref = {CACECI MS, 1984, BYTE MAY, P340 ; CANTOR CR, 1980, BIOPHYSICAL CHEM 3, CH20 ; CLAESSON S, 1976, CHEM SCR, V9, P18 ; DAVISON P, 1982, SOC PET ENG J JUN, P363 ; DUBOIS M, 1956, ANAL CHEM, V28, P350 ; FOSS P, 1987, CARBOHYD POLYM, V7, P421 ; FRANGOU SA, 1982, J POLYM SCI POL LETT, V20, P531 ; GEKKO K, 1985, INT J BIOL MACROMOL, V7, P299 ; GILL SJ, 1964, REV SCI INSTRUM, V35, P1281 ; GILL SJ, 1965, J PHYS CHEM-US, V69, P1515 ; GUNTER TE, 1972, BIOPOLYMERS, V11, P667 ; HAWLEY SA, 1974, BIOPOLYMERS, V13, P1417 ; HOLZWARTH G, 1976, BIOCHEMISTRY-US, V15, P4333 ; IGUSHI T, 1986, MAKROMOL CHEM-RAPID, V7, P497 ; KIERULF C, 1988, CARBOHYD POLYM, V9, P185 ; KITAGAWA H, 1985, CARBOHYD POLYM, V5, P407 ; KNUDSEN K, 1989, THESIS U TRONDHEIM N ; LAMBERT F, 1985, POLYMER, V26, P1549 ; LIU W, 1987, CARBOHYD RES, V160, P267 ; MORRIS ER, 1977, J MOL BIOL, V110, P1 ; NORTON IT, 1984, J MOL BIOL, V175, P371 ; OKUYAMA K, 1980, ACS SYM SER, V141, P411 ; REES DA, 1972, BIOCHEM J, V126, P257 ; RYLER RG, 1988, SPE RESERVOIR EN FEB, P23 ; SANDER FV, 1943, J BIOL CHEM, V148, P311 ; SERIGHT RS, 1985, 5TH SPE DOE S ENH OI ; STEVENS ES, 1987, CARBOHYD RES, V166, P181 ; STOKKE BT, 1989, ACS SYM SER, V396, P145 ; STOKKE BT, 1989, BIOPOLYMERS, V28, P617 ; SUTHERLAND IW, 1984, CARBOHYD RES, V131, P93 ; SUZUKI K, 1972, B CHEM SOC JPN, V45, P336 ; WEAST RC, 1982, HDB CHEM PHYSICS, V62, F76}, interhash = {498cde254bd23f7b6f2ef0f6856e86fc}, intrahash = {cb1e7f8fa4e427e3ffdd58be6ec84ae6}, isifile-dt = {Article}, isifile-ga = {FB658}, isifile-j9 = {J APPL POLYM SCI}, isifile-nr = {32}, isifile-pi = {NEW YORK}, isifile-rp = {STOKKE, BT, UNIV TRONDHEIM,NORWEGIAN INST TECHNOL,DEPT PHYS & ; MATH,NORWEGIAN BIOPOLYMER LAB,N-7034 TRONDHEIM,NORWAY.}, isifile-sc = {Polymer Science}, isifile-tc = {3}, issn = {0021-8995}, journal = {J. Appl. Polym. Sci.}, keywords = {;; [ISI:] conformation; electron-microscopy; polysaccharide; thermal-stability; transition}, language = {English}, month = {APR 5}, number = 7, owner = {phpts}, pages = {2063 -- 2071}, publisher = {JOHN WILEY \& SONS INC}, size = {9 p.}, sourceid = {ISI:A1991FB65800034}, timestamp = {2011-11-04T13:47:24.000+0100}, title = {OPTICAL-ROTATION OF DILUTE AQUEOUS XANTHAN SOLUTIONS AT ELEVATED HYDROSTATIC-PRESSURE}, volume = 42, year = 1991 }