Study On Thermodynamic Properties Of Rosin And Its Derivatives

Rosin is natural renewable resources that distilled by rosin,it is mixture of all kinds of resin acid.Their formula is C19H29COOH,The structure of 13 kinds of them has been determined.Rosin has many excellent properties because of the characteristic of the structure.So it is widely used in coating,rubber,paper,soap and adhesive industries.In order to broaden the purpose of the rosin to improve the value of it,rosin modified must to be studied.And in the study of rosin modified need a detailed understanding of the nature of rosin,especially in terms of the basic physical properties and thermal chemical properties.For this purpse.this paper mainly study basis of physical property and thermal chemical properties of six kinds of resin composition and two kinds of rosin acid derivatives.The study included the following contents:(1)Different group contribution method(Joback method and CG method)were used on pure components of turpentine basic physical property estimation,included melting point,boiling point,critical temperature,critical pressure,and critical volume;Then using the Joback method and CG method on the turpentine components thermochemical properties calculation,included the standard formation enthalpy,standard entropy,heat capacity at constant pressure and the standard Gibbs free energy.(2)Directly isolated from refined rosin of pinus elliottii pimaric acid.by using different piinaric acid isobutyl alcohol amine rapid selective principle into salt.By the method of recrystallization Malay raw pimaric acid and propylene pimaric acid crude products for purification experiment.relatively high product purity was obtained.(3)Oxygen bomb calorimeter was used to determine constant volume combustion heat,the results follows:Qv(isopimaric acid)=-11508kJ.mol-1、Qv(Propylene pimaric acid)=-12823.25 kJ.mol-1、Qv cmaleopimaricacid)=-12471.04kJ.mol-1。constant pressure heat of combustion,standard molar combustion enthalpy and standard molar enthalpy of isopimric cid,propylene pimaric acid and malay pimaric acid.(4)Differential scanning calorimetry(DSC)was used to determine dehydroabietic acid melting point,melting enthalpy and heat capacity,the DSC method was used to determine isopimric acid,propylene pimaric acid and malay pimaric acid.heat capacity,and using the standard material to test the reliability of the method.