| 摘要: | 一次性塑膠製品所引發的環境議題受到各國廣泛的關注，進而被禁用及取代，聚乳 酸塑膠成為許多產品轉為使用的替代方案。聚乳酸塑膠在具有適當溫度及濕度的堆肥場 中，會快速地被微生物分解，但對照全球的使用量，仍需要大面積的土地作為堆肥使用。 本研究旨在探討不同水體中的聚乳酸塑膠分解及老化情形，以及其吸附重金屬之情形， 用以推論未進入回收體系的聚乳酸塑膠其對環境及生物體的危害程度。
本研究將 PLA 塑膠片置於三種老化環境(無照光 25°C、60°C及有照光 60°C)，搭 配不同的暴露環境(空氣、去離子水、人工海水、人工淡水及人工淡水加腐植酸)，分別 老化 5、10、15、20 及 30 天後進行物性分析，透過 PLA 分子量的下降計算其水解反應。 而後取老化 30 天後的塑膠片，進行銅及鉛的吸附實驗。;The environmental issues caused by single-use plastic products have received extensive attention from various countries, and have been banned and replaced. Polylactic acid plastic has become an alternative for many products to be used. PLA plastics are rapidly decomposed by microorganisms in a compost field with appropriate temperature and humidity, but compared with the global usage, a large area of land is still required for composting. The purpose of this study is to investigate the decomposition and aging of PLA plastics in different water bodies, as well as their adsorption of heavy metals, in order to infer the degree of harm to the environment and organisms of PLA plastics that do not enter the recycling system.
In this study, PLA plastic sheets were placed in three aging environments (25°C without light, 60°C, and 60°C with light), with different exposure environments (air, deionized water, artificial seawater, artificial fresh water, and artificial fresh water plus humic acid). , respectively, after 5, 10, 15, 20 and 30 days of aging, the physical properties were analyzed, and the hydrolysis reaction was calculated through the decrease of the molecular weight of PLA. Then, the plastic sheets aged for 30 days were taken to carry out the adsorption experiments of copper and lead. |
