Application Of Chitosan-PLGA Nano/micro Encapsulated Fragrance In Aromatic Wallpaper And Study On Its Sustained Release Performance

Aromatic wallpaper serves as a kind of functional adornment wallpaper,because the aroma with peculiar natural aroma material,could improve living environment,cheerful mood,and have certain health care function.Therefore,it has higher market competition ability and latent value than traditional adornment wallpaper.On the other hand,the fragrant composition of aromatic wallpaper is usually essential oil,which is susceptible to temperature,light,p H and other environmental effects.Encapsulation techniques are often used to encapsulate the active ingredients of fragrances.However,some microcapsule materials are nondegradable or the degradation is very slow,resulting in adverse effects on the environments.In order to solve this problem,the choice of microcapsule wall material is given priority to the excellent performance,biodegradable and pollution-friendly materials.Amphiphilic block copolymer PLGA has good biological solubility and biodegradability,the degradation products are safe and non-toxic.In this paper,PLGA nano/microcapsules fragrance was prepared by a improved emulsifying solvent volatilization method.At the same time,the nano/micro particles were modified by chitosan,aiming to improve the loading capacity and adsorption performance for the preparation of aromatic wallpaper.The single-factor analysis method was used to explore the influence factors of particle size and loading capacity of nano/microcapsule fragrance.The block ratio of PLGA was determined to be 75:25,PVA concentration was 1%,the ratio of wall and core material was 1:1,the stirring speed was 800 rpm were found to be the best condition to preparate PLGA nano/microcapsules orange fragrance.On the other hand,the nano/microcapsules fragrance was characterized and analyzed by the relevant instruments,sunch as nano particle size instrument,TEM,SEM,FTIR.The results showed that the size of chitosanPLGA nano/microcapsules fragrance was 233.2-277.6 nm,the loading capacity was 19.17%-24.36%,and the adsorption capacity of aromatic wallpaper was 76.32 mg/g.After modified with chitosan,the adsorption capacity increased to 324.84 mg/g,which meant the absorption amount of aromatic wallpaper had a big increase(325.63%).In addition,GC-MS and the ultrafast GC Electronic Nose Heracles II were used for qualitative and quantitative analysis of sweet orange fragrance and aromatic wallpaper.The results showed that the composition content of sweet orange fragrance and aroma integrity of the aromatic wallpaper were good,and the process of fragrant finishing had little loss in terms to sweet orange fragrance.Through TGA,DSC,wearresisting experiment and tensile test,the heat resistance,friction resistance and tensile strength of the fragrant wallpaper were characterized.The results showed that the tensile strength and elongation at break of the fragrant wallpaper were 3.98% and 6.53% higher than that of the blank wallpaper,respectively,with a better wear-resistance.Through the quantitative analysis of key aroma substances and artificial sensory evaluation,the lasting time of this aromatic wallpaper is at least 6 months.