ABSTRACT Porous resorbable implants are of great interest since they may deliver bioactives or drugs, facilitate the transport of body fluids or degradation products and provide a favorable environment for cell attachment and growth. In this work we report on a method using concentrated emulsions to template interconnected solid foam materials and to produce highly porous poly(3-hydroxybutyrate) (PHB) materials. Porous PHB films were cast made from water-in-oil template emulsions including Span 80 and lithium sulphate. The films were characterized by SEM-EDX and DMA. The water uptake of the films was recorded in order to determine the fraction water available pores. The results show that the addition of lithium sulphate allows a fine tuning of the film morphology with respect to porosity and interconnected porous structure. The film porosity was determined to 51% ± 3%, 52% ± 3% and 45% ± 3% for the films made with 0%, 2.9% and 14.3% lithium sulphate in the template emulsion, respectively. The fraction water available pores was significantly lower, 11% ±3%, 38% ±12% and 48% ± 7% for films with 0%, 2.9% and 14.3% litium sulphate respectively. Differences in fraction water available pores and total porosity for the films reflects the film morphology and differences in pore interconnection.
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