| To solve the "white pollution", materials which is good in service and environment-friendly should be found to substitute the foamed plastic container. Among those new type of containers, paper-based containers are the most popular substitute of foamed plastic container, for they are mainly made of natural plant materials which are not only abundant in nature, but also can be degraded easily,While in practice, a lot of oil-proof and waterproof agents are added into pulp to perform better oil-proof or waterproof ability, which at the same time prevent the container from being degraded fast in natural. To solve the contradiction, it's important to research the mechanism of paper-based container's degradation in different environment.First, the alkaline sulfite reed pulp was used as main material and oil-proof agent of F-321and waterproof agent of HA-321 were used as the main chemical agents to research the effect of agents on the properties of paper-based container in service.The results showed that F-321and HA-321 can inform paper-based container good properties of oil-proof and waterproof performance. APAM could increase the remaining of F-321 and HA-321 in pulp. The optimum dosages was HA-321, 4%, F-321, 0.6%, APAM, 0.05% (to oven weight).Secondly, degradation experiment of paper-based container had been tested under UV light, heat or soil environments. The characters of cellulose under different degradation conditions were researched. The effects of waterproof agent and oil-proof agent on the degradation of container were also researched.The photolysis results showed that when paper-based containers were aged under UV light, they changed a lot from exterior to interior. When irradiated under UV light for 7 weeks, the brightness of samples decreased about 20%, and the DP decreased from 1124 to 600. The tensile strength decreased about 20-40%, and the weightlessness was about 10%. The content of long cellulose decreased, while the short cellulose which was about 0.2~1.0 mm long increased. When irradiated under UV light for 6 weeks, the crystallinity of samples increased from 71% to 75%.The thermolysis result showed that when paper-based container were degraded under high temperatures, the properties, such as brightness, DP, tensile strength of samples decreased. The higher the temperature was the faster the thermolysisprocessed. When the paper-based containers were aged under 100℃ for 16 days, the brightness decreased about 25%, DP decreased from 1124 to 600, the weightiness lost was about 12%~14%. While when samples were decomposed under 160℃ for 96 hours, the brightness decreased above 80%; the DP decreased from 1124 to 200; the tensile strength decreased about 59%~83%; the weightiness lost about 18%; the carbonyl group index increased; the crystallinity decreased; shorter cellulose which were about 0.2-0.6mm long increased.The TG of samples showed that when heated, the samples' thermolysis included two stages: In the initial stage of thermolysis (60℃~100℃), water molecules in the samples emerged firstly, which caused the weightiness of samples decreased about 4.77%~6.89%. When the temperature increased to 240℃~250℃I the samples decomposed quickly, and when the temperature increased to 340℃ -350℃, the samples degraded in the fastest velocity, and the weightiness of samples decreased fast. When the temperature increased to about 380℃, the thermolysis of paper-based container was almost finished, the weightiness decreased slowly with time going on.The biodegradation results in soil showed that when samples were buried into soil, they degraded fast. In the first 1-2 weeks, the color of samples became yellow obviously, and the surface of samples was attacked by mildew. With the time going on, samples broke up, and degraded completely finally. Samples pretreated under UV light for 7 weeks degraded faster in soil, and after 3 weeks, the DP decreased to about 200. While samples unpretreated by UV light degraded completely after being buried in soil for 5 weeks.In addition, the addi...
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