| Industry,the cyclohexanol and cyclohexanone which by nitric acid oxidation in the process of the production of adipic acid,also deputy produced a large number of glutaric acid,succinic acid and the mixture of adipic acid,which glutaric acid content in more than 60%,according to separating the refined preparation quality of glutaric acid is of great significance,but also for the realization of the glutaric acid base application exploration provides the raw material of polyester polyols.In this paper,the mixed dicarboxylic acid from the by-product of adipic acid device of henan nylon co which is used as raw material.First,high quality glutaric acid was obtained by gradient crystallization,and its purity reached more than 99.99%.Again with the purified glutaric acid as raw materials,and glycol under certain conditions by esterification,dehydration,condensation of the preparation of different molecular weight polyester polyol intermediates,diisocyanate with their reaction,preparation of polyurethane elastomer and adding suitable amount of chain extender,the ratio of raw materials,process method and additives is different,the properties of the polyester polyol,the performance won the different purpose of polyurethane.The conclusions are as following:(1)during the separation of glutaric acid,the semi-fine glutaric acid was obtained by gradient crystallization with water as the solvent.The optimum operating conditions: the ratio of material to water 2.8:1,after dissolved completely,crystallization 8 h under 27,get first centrifugal filt? er residue and filtrate;The first filtrate obtained was crystallized at a lower temperature for 6 h.After centrifugation,the semi-fine glutaric acid filter residue with a purity of more than 90% was obtained.The third recrystallization was carried out at a lower temperature,and more than 90% of the semi-fine pentaric acid filter residue was obtained by centrifugation.Dissolve half fine glutaric acid,under the appropriate water,adding 7.1%-7.5% activated carbon,under temperature 50 after decolorin? g time 2 h,condensed the solution to the appropriate proportion,crystallization under 27 ?,2 h,can obtain high purity of glutaric acid.(2)in the application exploration of glutaric acid base polyurethane,through the different alkyd ratio,esterification time,esterification temperature,polymerization time,polymerization temperature and the dosage of catalyst,obtain different molecular weight of glutaric acid propylene glycol ester(PPG),the synthesis of glutaric acid base polyurethane elastomer properties are different.The water content of the synthesized polyols is less than 0.05%.Its characteristic viscosity is above 0.64 dL/g.The tensile strength of PPG with different properties is over 10.68 MPa,while its hardness is between 70 and 80,and the elongation at break is slightly less than PPA.It is also found that the hardness of polyurethane elastomer is only related to the content of hard segment chain,and the higher the content of hard segment chain,the harder it is.The tensile strength of polyurethane elastomer decreased gradually with the increase of the molecular weight of polyurethane polyols,while the elongation at break increased gradually and the hardness decreased gradually.Comparing PPG with PPA polyurethane elastomer,from the macro perspective,PPG polyurethane elastomer than PPA polyurethane elastomer is slightly yellow,and the hardness significantly below PPA,and diisocyanate reaction intensity significantly greater than the PPA.It was concluded that the polyurethane elastomer prepared by PPG-2000 and PPA-3000 had similar correlation properties. |
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