The Research Of Phbh/cellulose Composite Packaging Materials

PHBH/cellulose composites were prepared by using two methods:First,PHBH and cellulose dissolved in trifluoroacetic acid,then the solution form PHBH/cellulose composite membrane by flowing spread molding;Second,NaOH/urea/water were used as the solvent to dissolve cellulose,the cellulose solution was used to prepare cellulose gel membrane,then the cellulose gel membrane permeated in PHBH/loroform solution to prepare PHBH/cellulose gel composite membrane.Two kinds of schemes of composite membrane were characterized by scanning electron microscope(SEM),foruier transform infrared(FTIR),mechanical properties,X-ray diffraction(XRD),thermogravimetric analysis(TGA),the moisture resistance,the oxygen resistance,degradability test,the main conclusions include:(1)The main conclusion of PHBH/cellulose composite membraneSurface scanning electron microscopy showed that the PHBH membrane surface possessed more pore,the cellulose membrane surface was smooth.50wt%cellulose composite membrane surface is rough,other composite membrane surface is smooth.Tensile section scanning electron microscope showed that the section structure of PHBH membrane is loose,the section structure of cellulose membrane was compact.The section of 80wt%and 90wt%cellulose composite membrane had a layered structure,no phase separation phenomenon produced;Foruier transform infrared showed that the level of the hydrogen bonding was best when the fiber content was 90wt%;Tensile results of composite materials showed that the tensile strength of PHBH/cellulose composite membrane showed increasing trend with the increase of cellulose content,90wt%cellulose composite membrane possessed the maximal tensile strength.The elongation at break of composite membrane showed a trend of decline with the increase of cellulose content,50wt%cellulose composite membrane reached maximal elongation at break;XRD showed that the position of the diffraction peak of pure cellulose membrane was close to the position of the diffraction peak of composite membrane;Thermogravimetric analysis showed that the thermal stability of PHBH/cellulose composite membrane was best when cellulose was 90wt%;The moisture resistance results showed that the moisture resistance gradually reduced with the increase of cellulose;The oxygen permeability results showed that the resistance of oxygen of 90wt%cellulose composite membrane was best;The mass loss results of composite degradation showed that the total mass loss of materials increased and then decreased after 15 days with the increase of cellulose,the mass loss of 90wt%cellulose composite membrane was the smallest,indicated 90wt%cellulose composite membrane had the smallest degradation rate.(2)The main conclusion of PHBH/cellulose gel composite membraneSurface scanning electron microscopy showed that composite surface was smooth and dense when cellulose content is low,the cellulose was obvious when cellulose content is higher.Tensile section scanning electron microscope showed that 80wt%cellulose composite membrane had a layer structure,PHBH fully infiltrated into cellulose gel membrane;FTIR showed that 80wt%cellulose composite membrane showed the best level of the hydrogen bonding;Tensile results of composite materials showed that the tensile strength of PHBH/cellulose gel composite membrane was increased and then reduced with the increase of cellulose content,80wt%cellulose gel composite membrane possessed the maximal tensile strength.The elongation at break of gel composite membrane showed a trend of decline with the increase of cellulose content;XRD showed that the diffraction peak position had a little change.Crystallization index of PHBH/cellulose gel composite membrane increased with cellulose content increased;Thermogravimetric analysis showed that the thermal stability of PHBH/cellulose gel composite membrane degraded significantly,80wt%cellulose gel composite membrane showed the best thermostability;The moisture resistance results showed that the water vapor permeability increased gradually with the increased of the cellulose content,the moisture resistance of cellulose gel membrane resistance was worst;The resistance of oxygen results showed that the oxygen permeability decreased and then increased with the increased of the cellulose content,the resistance of oxygen of 80wt%cellulose gel composite membrane resistance oxygen was best;PHBH/cellulose gel composite membrane degradation results showed that the mass loss of 80wt%cellulose gel composite was minimal in gel composite membrane,indicated 80wt%cellulose composite membrane had the smallest degradation rate.