EkoFoam

biodegradable polyester foams

EkoFoam is a newly developed biodegradable foam sheet based on new melt processing technology for polyesters.   Aliphatic polyesters, which are well known to have good biodegradability, are being used for various applications like mulch films, garbage bags and other disposable products.   However when they all are heated for foaming process, their melt strength is too low to produce foams having high expansion ratios.   By using our new melt processing technology, biodegradable foam sheets with high expansion ratios can be manufactured with aliphatic polyesters.

Biodegradability of EkoFoam

EkoFoam has a nearly perfect biodegradability and is the most environmentally friendly product because this is made by 100% naturally compostable polyesters, which are known to be degraded to water, carbon dioxide and other biomass by micro organism in the soil.

Fig. 1 shows that the biodegradation rate of EkoFoam is similar to that of cellulose that comes from natural resources.  And thus, EkoFoam has been proved to have excellent biodegradability and to be environmentally friendly product.

Fig. 1. Composting Test Results for Cellulose, PE(Polyethylene) and

 EkoFoam with aliphatic polyester.(The composting test was done by the Agency for Technology and Standard, Ministry of Commerce, Industry and Energy, Korea)

And the land filling tests on sheet type products are being done.  In Fig. 2, the changes of EkoFoam samples during land filling test are shown.

Considering that the test sample with the size of 20×30×20mm is thicker than normally used sheet type products with the thickness of 3 ~ 6mm, it may be expected that our sheet type products can be degraded faster in 3 or 4 months after land filling.

1 month                                   2 months                             3 months

4 months                             5 months                                  6 months

Fig. 2  Changes of EkoFoam during the Land Fill Test

Physical Properties of EkoFoam

EkoFoam manufactured with aliphatic polyester and their equivalent has fair to good mechanical properties compared with conventional polystyrene and polyethylene foams, especially with break strength, tensile strength and resilience.   In case by case, these properties are completely adjustable with changing the aliphatic polyester resin, introducing special fillers and/or controlling the expansion ratios during the foaming process.   In Table 1, the mechanical properties of EkoFoam are shown but these are not specified values, just typical values.

Table 1. Typicall Properties of EkoFoam

Application of EkoFoam

EkoFoam can be widely adapted to various purposes, mainly replacing the flexible PE(Polyethylene) foams, which are commonly used for packaging material for electronic goods, glass wares and food products but many countries have been regulating or prohibiting the usage of them because they are not biodegradable material, so their wastes have contaminated our environment.  In Fig. 3, various EkoFoam products are shown.

Fig. 3  Applications of EkoFoam