La Mantia Francesco Paolo, Ascione Laura, Mistretta Maria Chiara, Rapisarda Marco, Rizzarelli Paola
Dipartimento di Ingegneria, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Via Giusti 9, 55100 Firenze, Italy.
Polymers (Basel). 2020 Mar 30;12(4):753. doi: 10.3390/polym12040753.
Polymer films based on biodegradable polymers, polyethylene (PE) and modified PE with oxo-degradable additive were prepared by film blowing. Carbon black (1%) was added to all the films. Commercial biodegradable Ecovio and Mater-Bi samples were used. Mechanical properties, soil burial degradation and surface wettability were investigated, before and after UV irradiation. Chemical modifications induced by UV and soil degradation, or a synergic effect, were highlighted by Attenuated Total Reflection-Fourier Transform Infra-Red (ATR-FTIR). Photo-oxidized film samples with an elongation at break equal to 50% and 0.5 the initial value were selected for the soil burial degradation test at 30 °C. Weight loss measurements were used to follow biodegradation in soil. Predictably, the degradation in soil was higher for biodegradable polymer-based films than for the PE-based ones. UV irradiation increased surface wettability and encouraged the disintegration in soil of all the samples. In fact, photo-oxidation produced a molar mass reduction and hydrophilic end groups, thus increasing surface erosion and weight loss. This paper not only supplies new criteria to evaluate the performance of biodegradable films in agriculture, before and after lifetime, but also provides a comparative analysis on the soil burial degradation behaviour with traditional ones.
通过吹膜法制备了基于可生物降解聚合物、聚乙烯（PE）以及添加了氧化降解添加剂的改性PE的聚合物薄膜。所有薄膜中均添加了1%的炭黑。使用了商业可生物降解的Ecovio和Mater-Bi样品。对紫外线照射前后的机械性能、土壤掩埋降解和表面润湿性进行了研究。通过衰减全反射傅里叶变换红外光谱（ATR-FTIR）突出了紫外线和土壤降解引起的化学改性或协同效应。选择断裂伸长率等于初始值的50%和0.5的光氧化薄膜样品在30°C下进行土壤掩埋降解试验。采用失重测量法跟踪土壤中的生物降解情况。可以预见，基于可生物降解聚合物的薄膜在土壤中的降解程度高于基于PE的薄膜。紫外线照射提高了表面润湿性，并促进了所有样品在土壤中的分解。事实上，光氧化导致摩尔质量降低和亲水端基的产生，从而增加了表面侵蚀和失重。本文不仅提供了评估可生物降解薄膜在农业使用期前后性能的新标准，还对其与传统薄膜在土壤掩埋降解行为方面进行了比较分析。
