The Preparation Of Supported UV Absorber And Its Application In PBAT Films

Poly?butyleneadipate-co-terephthalate??PBAT?is widely used in the field of biodegradable film due to its good biodegradability and mechanical properties.However,PBAT's special structure makes it susceptible to UV aging,limiting its application.At present,the UV aging of polymer is mainly alleviated by adding UV-absorbers to PBAT in industry.However,the conventional UV-absorber has the disadvantages of low thermal stability,easy migration and decomposition,poor compatibility with the resin.Therefore,it has practical significance to develop a new type of UV-absorber for the promotion and use of PBAT.In this work,the supported UV-absorber,SiO₂-531,was prepared by solid-phase using2-hydorxy-4-octyloxybenzophenone?UV-531?as reactant and silica?SiO₂?as supporter.FT-IR,X-ray photoelectron spectroscopy and TGA were used to characterize the structure of SiO₂-531.The results showed that the preparation of SiO₂-531 was mainly attributed to the formation of ether bonds which caused by the dehydration reaction between hydroxyl groups of SiO₂ and phenolic hydroxyl groups of UV-531.Then,PBAT/SiO₂-531 and PBAT/SiO₂-N-0composite films were prepared by solution casting.The anti-UV aging behaviors?anti-migration properties,thermal stability and moisturizing properties of SiO₂-531 and SiO₂-N-0 in composite films were systematically studied.Then PBAT/SiO₂-531 composite films were prepared by using PBAT as the subtrate.The effects of supported UV-absorbers SiO₂-531 on the performances of PBAT composite films were investigated.It was shown that when the amount of SiO₂ and UV-531 are both 1%,supported UV-absorbers SiO₂-531significantly improves the anti-UV aging properties and the moisture retention of PBAT film and has better dispersion and distribution properties and migration resistance than the compounding system SiO₂/UV-531.In addition,the practicability of PBAT/SiO₂-531 film was further investigaed through exposure experiment under natural climate environmental conditions.It was found that the morphology of the film was retained after aging for 70 days,indicating the significance of PBAT/SiO₂-531 film in practical application.The supported UV-absorbers,SiO₂-N-0,was prepared by sol-gel methods using2,4-dihydroxybenzophenone?UV-0?as reactants and silica?SiO₂?as supporter.And FT-IR,X-ray photoelectron spectroscopy and TGA were used to characterize the structure of SiO₂-N-0.The results showed that UV-0 was chemically grafted on Si O₂ surface to form supported UV-absorber SiO₂-N-0 through the chemical linkage provided by coupling agent chloromethyltriethoxy-silane?NQ5151?.Then PBAT/SiO₂-N-0 composite films were prepared by using PBAT as the subtrate.The effects of supported UV-absorbers SiO₂-N-0 on the performances of PBAT composite films were investigated.The results show that when the amount of SiO₂ is 1%and the amount of UV-0 is 0.07%,SiO₂-N-0 can be better distributed and dispersed in PBAT films,and PBAT/SiO₂-N-0 film has better anti-UV aging properties and excellent migration resistance compared with the PBAT/SiO₂/UV-0 film.PBAT/SiO₂-531/328 composite film for aging experiments and peanut mulch was successfully prepared by a blown film forming production facility,and its mechanical properties and anti-aging properties were studied.Preliminary experimental results show that SiO₂-531/328 can be applied to the actual blown film production process of PBAT degradable films,and the obtained film has well mechanical properties and anti-ultraviolet aging performance.