A method for manufacturing a heat sealable polyester film is provided. A part of a recycled polyester material is physically reproduced to obtain physically regenerated polyester chips. Another part of a recycled polyester material is chemically reproduced to obtain chemically regenerated polyester chips. Modified polyester chips, the physically regenerated polyester chips and the chemically regenerated polyester chips are mixed to form a raw material mixture, and the modified polyester chips are formed from the recycled polyester material. The raw material mixture is used to form a heat sealable layer. A base layer is disposed onto the heat sealable layer so as to obtain the heat sealable polyester film. A heat sealing temperature of the heat sealable polyester film ranges from 120 C. to 230 C.

In a first aspect, the present disclosure relates to a decorative patch, wherein the decorative patch comprises a first layer and a transparent second layer, wherein the first layer and transparent second layer form a first structure comprising at least one cavity, wherein the at least one cavity comprises an aqueous fluid, and wherein the aqueous fluid comprises a plurality of chloroplasts, a glucose oxidase for converting glucose to gluconolactone, and a monomer or oligomer capable of reacting with gluconolactone.

An ultra-fast marine-biodegradable composite film can include at least one water-soluble layer, and at least one marine-biodegradable layer disposed in contact with the at least one water-soluble layer. The composite film can include a plurality of the water-soluble layer, and a plurality of the marine-biodegradable layer interspaced between the marine-biodegradable layers. The composite film may be used for packaging, including food packaging. Methods of preparing an ultra-fast marine-biodegradable composite film are also disclosed.