Lucia H. Innocentini-Mei

Comparative study of processing methods for starch/gelatin films

In this work, the influence of processing methods on the properties of starch/gelatin films plasticized with glycerol and sorbitol is reported. Four different processing techniques: casting; pressing; pressing followed by blowing and extrusion followed by blowing were evaluated. Bioplastics prepared by casting were homogeneous and transparent with lower opacity and water vapor permeability (WVP) values when compared to films prepared by other techniques. Among the cast films studied, those with 3% lipophilic starch, in 1:1 proportions and plasticized with sorbitol, showed lower WVP values and higher tensile strength (TS). Films obtained by pressing and blowing showed little expansion during blow, had cracks in the surface, low TS and higher WVP. These films were the only samples to show crystallinity as determined by thermal analysis and X-ray diffraction. In conclusion, different processing techniques have significantly affected the properties of these films.

Processing and characterization of composites of poly(3-hydroxybutyrate-co-hydroxyvalerate) and lignin from sugar cane bagasse

A biodegradable polymer composite containing lignin from sugarcane bagasse and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was produced and characterized in terms of its thermal, morphological, and mechanical properties. For comparison with the properties of the composites, the properties of the isolated composite components (lignin and PHBV) were also determined. The characterizations were carried out by Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and mechanical properties. In the micrograph images, no physical contact between filler and matrix was verified. The thermal decomposition profiles of composites depend on the lignin/PHBV proportions, and their residual mass increased as a function of lignin amount. Higher temperatures were necessary to promote PHBV crystallization in the presence of lignin. However, the crystalline degree of composites was not affected by the lignin. The results obtained in the mechanical tests showed that the lignin addition caused a decrease of mechanical properties.

Silica immobilized enzyme catalyzed removal of chlorolignins from eucalyptus kraft effluent

Abstract Immobilization of lignin peroxidases type I, II, III, lyophilized fungal culture from Chrysonilia sitophila (TFB-27441) and horseradish peroxidase (HRP) on activated silica were carried out. Immobilized HRP gave 37% decolonization, with 60% mineralization. The most efficient lignin peroxidase was LiP type III with 20% mineralization, 65% COD reduction and 12% decolonization. None of the enzymes which were immobilized exhibited loss of activities after being frozen for 2 months or after 5 d contact with a kraft effluent. Silica appeared as an important immobilizing support in the industrial use of oxidoreductases in environnmental studies.

Phenoloxidases and hydrolases from Pycnoporus sanguineus (UEC-2050 strain): applications

Abstract The basidiomycete, Pycnoporus sanguineus , possess lignin peroxidase, Mn-peroxidase, phenoloxidases, xylanase and β-glucosidase activities when grown on malt extract. A large induction, mainly in laccase activity with malt extract/E 1 effluent (46 U l −1 ), malt extract (100 U l −1 ) and malt extract/ Eucalyptus grandis wood (61 U l −1 ) as carbon sources was found. The phenoloxidase capacity along with the presence of beta-glucosidase P. sanguineus led us investigate its use in effluent treatment. This fungus was efficient not only in chromophore group transformations but also in the reduction of phenols, biochemical and chemical oxygen demands, and toxicity.

A new alternative process for Kraft E1 effluent treatment

Lentinus edodes (UEC-2019 strain) was selected after screening 51 ligninolytic strains of fungi for their ability to decolorize phenolic industrial effluent with high content of lignin peroxidases, Mn-peroxidases and beta-glucosidases. This strain removed 73 % of color in theEucalyptus Kraft E1 effluent in 5 days without any additional carbon sources. A 13% mycelial adsorption was found. Correlation between mass loss, COD, TOC and decolorization was observed. When an effluent pre-irradiated (10 min) in the presence of ZnO was treated withL. edodes, a marked enhancement of the decolorization at 48 h was obtained.L. edodes is an active fungus in this pre-treatment and biobleaching process. The combined photo-biological decolorization procedure appears to be an efficient decontamination method with great potential in industrial effluent treatment.

Synthesis of porous macrospheres from amino-polymers

Abstract Porous macrospheres with controlled diameter were produced using N-methylolacrylamide and urea–formaldehyde resins synthesized in our laboratories. Hot silicon oil was used to form the porous macrospheres which were characterized by using infrared spectroscopy (FTIR), scanning electron microscopy, mercury porosimetry and surface area determination (BET). Porous macrospheres of amino-polymers were used as support in immunoassays type ELISA (enzyme linked immunosorbent assay) in which mouse immunoglobulin (IgG) was immobilized, and detected by rabbit anti-mouse immunoglobulin (a-IgG) labeled with horseradish peroxidase. Responses were obtained up to a dilution ratio of 1:4000 of the conjugate standard (1 mg/ml) and 10 μ g/ml of IgG solution to recover the spheres in pH=4.5.

Recent Studies on Soy Protein Based Blends, Composites and Nanocomposites

With the environmental appeal around the planet for a sustainable development, there is the need to develop new materials from renewable resources, which can be degraded in a short time in the environment, thereby maintaining the proper balance of the carbon cycle. The utilization of hydrocolloids, such as soy protein, to prepare biodegradable materials with suitable properties, has been a great challenge for the scientific community, since these materials do not possess all the desirable characteristics of the synthetic polymers, being mostly often, highly hydrophilic and also presenting poor mechanical properties to be used as engineering’s materials. In this context, the studies with application of nanotechnology to biodegradable polymers can open new possibilities to improve not only the properties of these materials, but also its efficiency.

CHAPTER 16:Natural Rubber Blends with Biopolymers

The mechanical properties of biopolymers, such as polyesters, polysaccharides and proteins, can pose issues that need to be overcome. These issues are stiffness, brittleness, poor elongation to break and relatively high cost. Whereas, natural rubber exhibits a unique combination of toughness, flexibility, biocompatibility and biodegradability that together with its low cost makes it an ideal candidate to overcome the drawbacks of the above-mentioned biopolymers. However biopolymers/natural rubber blends normally do not lead to miscible systems, alternative approaches have been used to establish some compatibility between them, in an attempt to create ‘new’ materials with advanced functionalities. For instance, in situ reactive blend is sometimes a good alternative to improve compatibility or the use of a third polymer as a compatibilizer. It is also possible to use both aforementioned alternatives, i.e. combination of reactive blending with compatibilizers, the choice being guided by the system and the biopolymer used. This chapter is designed to provide an overview of the state of the art of blends between natural rubber and biopolymers. The preparation or processing of the blends and the structure–property relationship are emphasized, as well as their industrial applications.