Study On The Treatment Method And Mechanism Of Mink Splitting

Mink is the fur material of slap-up fur,in production and the treatment of shabby goods exists the problems of resource utilization of protein waste,including hide fiber and wool fiber.In this study,the use of hydrogen peroxide as a green oxidizing agent onto mink splitting producing self-crosslinking which provided theoretical basis for the highvalue utilization of mink wastes.The physical-chemical properties of mink splitting were studied from amino acid composition,chemical constituent,hygienic property,mechanical behavior and the parametric variation in the process of washing and rewetting.It was found that:(1)The protein of mink splitting is composed of 16 kinds amino acids,neutral amino acids accounted for 77.35%,acidic amino acids and basic amino acids were 13.87% and 8.78%;(2)C,N and O are the main elements of skin,followed by S,C l,P and Al;(3)After washing,the mink splitting were increased in volatiles,methylene chloride extract,water absorbency,shrinkage temperature,while total ash,the contents of water soluble substances,water vapor permeability,tear resistance and tensile strength were declined;(4)Dehydration is mainly caused by thickness reduction,the area varies little;(5)The washing methods of continue stirring,stirring and static soaking can accelerate the exudation of water soluble substance,the state of the solution is balanced with 3 times of repeated,it needs 5 times with static soaking method;(6)The absorbates in the ultraviolet region were washed.The use of hydrogen peroxide as an oxidizing agent onto mink splitting which producing self-crosslinking was studied by total reflection infrared spectra,fluorescence spectrum,contact angle and thermal properties.The mechanism of self-crosslinking of hydrogen peroxide oxidating skin was analyzed.It was found that,hydroxide groups on the collagen side-chains can be oxidized to aldehyde or carboxyl groups by hydrogen peroxide in alkaline environment.These oxidized groups can crosslink with functional groups on collagen by covalent bond and ionic bond,improving thermal stability and hydrophobicity of the skin.The operation condition of using hydrogen peroxide solution at 18.95 wt% basing on the skin weight,the reaction temperature of 35?,the reaction temperature of 4h,oxidative self-crosslinking of skin fiber was the strongest and achieved the highest thermal stability.Collagen was extracted from mink skin solid waste by pepsin method.The extracted collagen was characterized by chemical constituent,ultraviolet and infrared spectroscopy analysis,isoelectric point and thermal stability.It was found that,the extraction rate of collagen was 18.15%,the volatiles,methylene chloride extract and total ash were 2.54%,8.66% and 1.34%;The isoelectric point(pI)of collagen was 6.45,which was weak acidic,the thermal denaturation temperature was 80.4? and the thermal degradation temperature was 121?.In this study,the use of hydrogen peroxide as an oxidizing agent onto collagen producing self-crosslinking which extracting from mink solid waste was studied by infrared spectroscopy,fluorescence spectrum,thermal properties and flowing deformation.The effect of hydrogen peroxide dosage,reaction temperature and reaction time on the degree of oxidative self-crosslinking of collagen was analyzed by the changes of molecular structure and thermal stability.It was found that,hydroxide groups on the collagen side-chains can be oxidized to aldehyde groups and carboxyl groups by hydrogen peroxide in alkaline environment.These oxidized groups can crosslink with functional groups on collagen by covalent bond and ionic bond,changing collagen molecular structure and improving thermal stability.When the dosage of hydrogen peroxide was 14.74%,reaction temperature was 40? and the reaction time was 3h,the oxidative self-crosslinking of collagen was the strongest.the use of hydrogen peroxide as an oxidizing agent onto gelatin producing selfcrosslinking was studied by thermal properties,contact angle and flowing deformation.The effect of hydrogen peroxide dosage,reaction temperature on the degree of oxidative self-crosslinking of gelatin was analyzed by the changes of thermal stability of gelatin film,the number of polar groups on the surface of gelatin film and the change of flowing deformation characteristics.When the dosage of hydrogen peroxide was 29%,reaction temperature was 40?,the oxidative self-crosslinking of gelatin was the strongest.