welan gum

{{Chembox

| verifiedrevid = 429643136

| Reference =

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|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| CASNo = 96949-22-3

| EINECS = 619-250-2

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|Section2={{Chembox Properties

| Formula =

| Density = 26.25 lbs/ft³ (bulk)

| Appearance = white to cream colored powder

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|Section7={{Chembox Hazards

| ExternalSDS = [http://www.welangum.com/content/Welan_Gum_MSDS.pdf]

| NFPA-H = 1

| NFPA-F = 1

| NFPA-R = 0

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Welan gum is an exopolysaccharide used as a rheology modifier in industrial applications such as cement manufacturing.{{cite patent |country=US|number=5004506|status=patent| title = Welan gum in cement compositions | gdate =2 April 1991 | inventor = Allen, Floyd L. |inventor2=Best, Glen H. |inventor3=Lindroth, Thomas A. | assign1 = Merck & Co., Inc.}} It is produced by fermentation of sugar by bacteria of the genus Alcaligenes. The molecule consists of repeating tetrasaccharide units with single branches of L-mannose or L-rhamnose.{{cite journal|last1=Kaur|first1=Varinder|last2=Bera|first2=Manav B.|last3=Panesar|first3=Parmjit S.|last4=Kumar|first4=Harish|last5=Kennedy|first5=J.F.|title=Welan gum: Microbial production, characterization, and applications|journal=International Journal of Biological Macromolecules|volume=65|year=2014|pages=454–461|issn=0141-8130|doi=10.1016/j.ijbiomac.2014.01.061|pmid=24508918}} In solution, the gum retains viscosity at elevated temperature, and is stable in a wide pH range, in the presence of calcium ion, and with high concentration of glycols.{{Cite web|url=http://www.cpkelco.com/products-welan-gum.html |title=CP Kelco Welan Gum

| publisher=CP Kelco |accessdate=17 Sep 2010 }}{{Cite web|url=http://www.colltec.de/Home_english/Welan_Gum/welan_gum.html |title=Welan gum |publisher=Colltec |accessdate=17 Sep 2010}}{{Cite web|url=http://www.welangum.com/ |title=Welan gum |publisher=Fritz Industries |accessdate= 17 Sep 2010}}