User:Mobeen Ashraf/Notebook/Chem-581/2012/09/07
Experimental Chemistry | Main project page Previous entry Next entry |
ObjectiveSolubility Test for Cross-linked and Not Cross-Linked PVOH Films DescriptionSolubility Test for Non Cross-Linked and Cross Linked PVOH Films. Three films of PVOH were made and were labelled as A, B, and C. A contains .5 g PVOH, MW of 22,000 in 5 ml of water. B contains 0.5 g PVOH, MW of 22,000, in 5 ml of water and phosphoric acid. C contains 0.5 g PVOH, MW of 22,000 in 5 ml of water, maleic acid, and phosphoric acid. We also prepared thin films of 0.1 g PVOH, having the molar masses of 22,000 and 100,000. Cross linking of the films were done by heating films into the oven set up at a temperature of 120 degree Celsius for 90 mins. Solubility Test with out Heating (dry films): 0.1014 g of A, starting time: 1:45 pm, ending time: 2:17 pm > Completely Soluble 0.1000 g of B, starting time: 1:20 pm, ending time: 1:45 pm > Completely Soluble 0.1051 g of C, starting time: 2:17 pm, ending time: 2:35 pm > Completely Soluble Solubility Test with the Oven Films (Cross-Linked): 0.1 g of A, starting time: 2:35 pm, ending time: 3:00 pm > completely soluble 0.1 g of B, starting time: 3:00 pm, ending time: 3:30 pm > completely soluble 0.1 g of C, starting time: 3:00 pm, ending time: 3:30 pm > not dissolved, insoluble Data
NotesHeating PVOH in presence of a cross linker, promotes cross-linking. Heat imparts and induces high degree of cross linking. Fully cross-linked films are not soluble in water solution and are durable as well as heat resistant. |