1,2,3-Propanetricarboxylic

Table 8. Thermodynamic parameters of the coil-to-helix transition of collagen-model peptides, covalently linked with 1,2,3-propanetricarboxylic acid (PTC) and Lys-Lys, respectively. Solvent 1% aqueous acetic arid (pH 3.0)...

CN 2-hydroxy-/V,/V,/V-lrimethylethanaminium salt with 2-hydroxy-1,2,3-propanetricarboxylic acid (1 1)... 

Citric acid monohydrate (8) 1,2, 3-Propanetricarboxylic acid, 2-hydroxy-, monohydrate (9) (5949-29-1)... 

The gel point is usually determined experimentally as that point in the reaction at which the reacting mixture loses fluidity as indicated by the failure of bubbles to rise in it. Experimental observations of the gel point in a number of systems have confirmed the general utility of the Carothers and statistical approaches. Thus in the reactions of glycerol (a triol) with equivalent amounts of several diacids, the gel point was observed at an extent of reaction of 0.765 [Kienle and Petke, 1940, 1941], The predicted values of pc, are 0.709 and 0.833 from Eqs. 148 (statistical) and 2-139 (Carothers), respectively. Flory [1941] studied several systems composed of diethylene glycol (/ = 2), 1,2,3-propanetricarboxylic acid (/ = 3), and either succinic or adipic acid (/ = 2) with both stoichiometric and nonstoichiometric amounts of hydroxyl and carboxyl groups. Some of the experimentally observed pc values are shown in Table 2-9 along with the corresponding theoretical values calculated by both the Carothers and statistical equations. 

TABLE 2-9 Gel Point Determinations for Mixture of 1,2,3-Propanetricarboxylic Acid, Diethylene Glycol, and Either Adipic or Succinic Acid"... 

N1 - 1,2,3-PROPANETRICARBOXYLIC ACIO, 2-HYDROXY-, TRILITHIUH SALT, HYDRATE... 

N1 - PYRROLIDINE l-(2-(4-Cl-C4-liETH0XYPHENYLI-2-NITR0-2-PHENYLETHENYL)PHEN0XY)ETMY-U- 2-HYDR0XY-1,2,3-PROPANETRICARBOXYLATE (i l)... 

E.57) (E.57) 1,2,3-Propanetricarboxylic acid, 2-hydroxy-, citric acid [77-92-9] FEMA 2306... 

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