Biodegradable resin composition and molded body and production method thereof

Abstract

There is disclosed a biodegradable resin composition containing 100 parts by mass of a biodegradable polyester resin containing not less than 50% by mass of polylactic acid, 0.1 to 10 parts by mass of a layered silicate, 0.1 to 5 parts by mass of a carbodiimide compound and 0.01 to 5 parts by mass of a phosphite organic compound. Alternatively, the biodegradable resin composition contains a phosphite organic compound and at least one additive selected from the group consisting of a hindered phenol compound, a benzotriazole compound, a triazine compound and a hindered amine compound in an amount of 0.01 to 5 parts by mass in total, instead of containing 0.01 to 5 parts by mass of the phosphite organic compound.

Description

TECHNICAL FIELD[0001]The present invention relates to a biodegradable resin composition having excellent color tone, strength and gas barrier property and having improved durability under a moisture heat condition, a molded body made of the composition, and a production method of the composition.BACKGROUND ART[0002]In recent years, biodegradable resins typified by polylactic acid have attracted attention from the viewpoint of environmental conservation. Of the biodegradable resins, the polylactic acid is highly useful, because the polylactic acid has excellent transparency, is one of the most heat-resistant resins, is less costly due to the mass-producibility from vegetable-derived materials such as corn and sweet potato, and can contribute also to reduction of oil materials. However, when a molded body is produced by only the biodegradable resin, the molded body has insufficient long term storage stability and moisture heat resistance to cause problems such as the reduction of the ...

AI Technical Summary

Benefits of technology

[0026]The present invention can provide a biodegradable resin composition having excellent color tone, strength and gas barrier property, maintaining strength and molecular weight for a long period of time even in high temperature and high humidity, and suppressing the generation of deposited substances such as low-molecular weight substances and metal salts of polylactic acid. This resin composition can be used for various types of molded bodies, and can be well used for various applications. The resin composition of the present invention, which has biodegradability, can be composted when being discarded. Therefore, the resin composition can be reused as a fertilizer, and the amount of garbage can be reduced. The polylactic acid, which is generally produced from raw materials derived from corn and sweet potato or the like, can contribute to the prevention of depletion of petroleum resources.

Problems solved by technology

However, when a molded body is produced by only the biodegradable resin, the molded body has insufficient long term storage stability and moisture heat resistance to cause problems such as the reduction of the strength and molecular weight caused by deterioration and the deteriorated appearance caused by the reduction of the molecular weight.

Therefore, the molded body cannot endure applications where the molded body is repeatedly-used and prolonged use.