申请人:KAO CORPORATION
公开号:EP1746136A1
公开(公告)日:2007-01-24
The present invention relates to a method of producing a biodegradable resin composition, which includes step (1) of mixing a biodegradable resin, a plasticizer, and a crystal nucleating agent with one another at the melting point (Tm) of the biodegradable resin or more, wherein the crystal nucleating agent is an aliphatic compound having, in its molecule, two or more of at least one group selected from an ester group, a hydroxyl group and an amide group, and step (2) of thermally treating the resulting biodegradable resin composition at a temperature of from the glass transition temperature (Tg) to less than Tm of the composition, as well as a biodegradable resin composition, which contains a biodegradable resin, a plasticizer, and the above crystal nucleating agent, and which satisfies the following conditions: the haze thereof with a thickness of 0.5 mm after thermal treatment at 60°C for 36 or 60 hours is 20% or less; the storage elastic modulus (E') at a temperature of 25°C and a frequency of 50 Hz is 1 × 108 to 2 × 109 Pa; and the storage elastic modulus (E') at a temperature of 60°C and a frequency of 50 Hz is 1 × 107 to 1 × 109 Pa.
本发明涉及一种生产可生物降解树脂组合物的方法,该方法包括步骤(1)在可生物降解树脂的熔点(Tm)或更高的温度下将可生物降解树脂、增塑剂和晶核剂相互混合,其中晶核剂是一种脂肪族化合物,在其分子中至少有两个或更多的基团,这些基团选自酯基,羟基和酰胺基;以及步骤(2)在组合物的玻璃化温度(Tg)至低于Tm的温度下对所得到的可生物降解树脂组合物进行热处理、步骤(2)在该组合物的玻璃化温度(Tg)至低于 Tm 的温度下热处理得到的可生物降解树脂组合物,以及可生物降解树脂组合物,该组合物包含可生物降解树脂、增塑剂和上述晶核剂,并满足以下条件:在 60°C 热处理后,其雾度厚度为 0.5 mm 的雾度为 20% 或更小;在温度为 25°C 和频率为 50 Hz 时,储存弹性模量(E')为 1 × 108 至 2 × 109 Pa;在温度为 60°C 和频率为 50 Hz 时,储存弹性模量(E')为 1 × 107 至 1 × 109 Pa。