Preparation And Adhesion Strength Of Composites Based On Modified Nano-titanium Dioxide/Modified Starch/Chitosan Films And Paper

In this study,the acetylated di-starch phosphate and chitosan were used as main film-forming materials to prepare blend films,and the preparation process of acetylated di-starch phosphate/chitosan blend films was optimized.Sodium laurate and ultrasonic-microwave were used as co-modification technology to modify nano-titanium dioxide.The effects on the the lipophilic degree of nano-titanium dioxide and properties of acetylated starch-phosphate/chitosan blend films at different conditions were investigated.On this basis,the composite material based on the blend film and kraft paper was prepared.The effects on composite material peel strength of adhesive concentration,amount and laminating temperature were studied.The research main content and conclusions are as follows:?1?Preparation of acetylated di-starch phosphate-chitosan blend films and optimization of its process conditionsAcetylated di-starch phosphate and chitosan were used as film-forming substrates.Through single-factor experiments,the effects of mass concentration of acetylated di-starch phosphate,chitosan mass concentration and glycerol mass concentration on the mechanical properties,water barrier properties and water-solubility of the blend films were investigated.The optimum parameters of the preparation of the blend film were obtained by response surface method optimization test:the mass concentration of acetylated di-starch phosphate was 4.00%,the mass concentration of chitosan was2.04%,the mass concentration of glycerol was 1.28%,corresponding to the blend films of the theoretical values of tensile strength,elongation at break,water vapor permeability,and water solubility were 23.43 MPa,78.42%,1.29×10^-12g·cm^-1·s^-1·Pa^-1and 30.22%,respectively.The results of fourier transform infrared spectroscopy showed that acetylated di-starch phosphate and chitosan had strong hydrogen bond,which indicated that acetylated di-starch phosphate and chitosan had good biocompatibility.The scanning electron microscopy results showed that the surface of the blend film was smooth and flat,and the components of the films were uniformly mixed.No particles or agglomerates were present,which proved that the acetylated diamyl phosphate and chitosan had good compatibility.?2?Sodium laurate modified nano-titanium dioxideUltrasound-microwave assisted sodium laurate was used to modify nano-titanium dioxide.The results showed that when the pH was 5,the ultrasonic-microwave synergistic action time was 15 min and the sodium laurate concentration was 15%,the highest the lipophilic degree of isnano-titanium dioxid was 78.2%.At this time,nano-titanium dioxide had the strongest hydrophobicity.The results of fourier transform infrared spectroscopy and X-ray diffraction analysis showed that sodium laurate and the hydroxyl groups on the surface of nano-titanium dioxide had chemical reaction,which existed on the surface of nano-titanium dioxide and did not affect the crystal structure of nano-titanium dioxide.The results of scanning electron microscope analysis showed that modified nano-TiO₂ by sodium laurate,the degree of self-agglomeration of nano-particles was reduced,and the particles was more uniform and fine.When the concentration of sodium laurate was15%,the effect of modification was best.The results of thermogravimetric analysis showed that sodium laurate of the thermal stability was poor.Adding too much sodium laurate significantly reduceed the thermal stability of the nano-titanium dioxide.?3?Preparation and properties of the blend film with modified nano-titanium dioxideThe modified nano-titanium dioxide was added to the acetylated di-starch phosphate/chitosan blend film.The effects of modified nano-titanium dioxide addition and sodium laurate concentration on tensile strength,elongation at break,water vapor permeability and water solubility of the blend films were studied.The modified nano-titanium dioxide was added in an amount of 3%and sodium laurate concentration at15%,the blend film had the best performance.At this time,the corresponding values of tensile strength,elongation at break,water vapor permeability,and water solubility of the blend filmd were 31.66 MPa,70.93%,and 0.92×10^-12·g·cm^-1·s^-1·Pa^-1 and 23.06%,respectively.?4?Preparation and adhesive strength of the blend film and kraft paper compositesThe composite material was combined with the blend film and kraft paper.The acetylated starch phosphate was used as binder and was coated on the kraft paper.The composite material has both the high barrier property of the blend film and the high mechanical and plasticity of paper.The effects on the adhesive strength of adhesive concentration,adhesive amount,and laminating temperature of the composite material were investigated.The results showed that when adhesive concentration was 4%,adhesive dosage was 12 mL,and the laminating temperature was 160°C,the blend film and kraft paper had the highest peeling degree of 1.55 N.