The problem of improper disposal of polymeric waste is increasingly in present. Thus, the use of biodegradable polymers is a good alternative, especially for packaging. Compostable and biodegradable polymers such as PHBV can be completely degraded, making them ideal. But the short processability window and fluid instability is an important drawback to the wider application of this polymer in pure form. Production of composite materials has been indicated as a possibility for using this polymer. One source of filler is cellulose, because besides being widely available from agroindustrial waste. In this context, the present work reports the formulation of rigid packaging with PHBV and cellulose waste. An analytical mill was used to promote the dispersion of cellulose fibers. In general, the cellulose fibers increased the Vicat softening point of the polymeric matrix. There were more crystalline structures, according to DSC, and a decrease in impact strength, probably due to increased crystallinity and agglomerate formation. The microscopic analysis indicated greater surface roughness of the composite due to the increase of fibers, resulting in increased contact angle.

Additive manufacture techniques using concentrated colloidal inks are a promising approach for creating three-dimensional (3D) calcium phosphates scaffolds for bone repair and regeneration. Among those, the direct-write assembly allows building scaffolds with precise size and geometry. In the present work, commercial β-TCP and HA were used to produce two types of colloidal ink. According to the ink composition used to build the scaffolds, two different groups were obtained. Group I: scaffolds produced with β-TCP-based ink; and Group II: scaffolds produced with biphasic CaP-based ink (BCP). The 3D scaffolds were assembled in a cylindrical shape (Φ = 8mm x H= 16 mm) with interconnected pore channels of approximately 500μm by robotic deposition of 64 layers using a robocasting machine. The mechanical compression property of the scaffolds was determined using universal testing machine. To assure the controlled geometry of the scaffolds, digital images were obtained by reconstructing each individual scan obtained with a micro-computed tomography. An optical contact angle measurement system was used to evaluate the wettability of the materials. After analyzing the results it was concluded that: the robocasting system is suitable for building 3D periodic calcium phosphates scaffolds; the direct-write assembly didn't change the hydrophilic characteristic of CaPs; and presented mean compressive strength around 11 MPa (β-TCP group) and 15 MPa (BCP group), which is compatible with trabecular bone.

Aging of cornstarch films prepared by casting was investigated. Water and glycerol-plasticized cornstarch films were stored at 50% relative humidity over a period of 330 days. Aging was followed by X-ray diffraction (XRD) and atomic force microscopy (AFM). XRD spectra indicated development of B-type crystallinity even for fresh films and that the crystallinity index increased from 0.06 to 0.28 as a function of storage time. AFM images of 270-day-old films revealed that the general morphology and the overall roughness have not changed due to aging. AFM phase contrast images at higher magnification showed an increasing number of ordered domains at the surface of these films, which may be attributed to recrystallization of amylose. No morphological change was observed at least at the surface of the granular region, which is enriched in amylopectin.

Misturas de amido de milho e água nas proporções 70:30, 80:20 e 90:10% (p/p) foram submetidas a processamento a 90°C, sob diferentes velocidades de rotação (20, 40, 80 e 100rpm), em câmara de mistura Rheomix 600 equipada com rotores do tipo "roller". A influência do teor de água e da velocidade de rotação dos rotores no processamento do amido de milho foi investigada por meio de curvas de torque e de temperatura fornecidas pelo reômetro de torque Rheocord 9000. Análises em Analisador Rápido de Viscosidade e por microscopia óptica de luz polarizada foram realizadas, a fim de complementar as informações registradas pelas curvas de torque e de temperatura. Os resultados mostraram que o teor de água e a rotação empregada no processamento exercem influência significativa nas características do amido processado. Os menores teores de água (10 e 20% p/p) e as velocidades de rotação mais elevadas (80 e 100rpm) contribuíram para a maior degradação do amido. Nas misturas com teor de água de 30% (p/p), sob as velocidades de rotação empregadas, a função plastificante da água contribuiu para minimizar o efeito do cisalhamento, já que a degradação do amido não foi observada. Nesses casos, a estrutura granular do amido foi preservada em grande parte durante o processamento.

Corn starch/water mixtures at compositions of 70:30, 80:20 and 90:10 (w/w %) were submitted to processing at 90ºC and different rates (20, 40, 80 and 100rpm) in an internal mixer (Rheomix 600), equipped with counter-rotating roller type rotors. The effect of the water content and of the rotation rate on the starch processing was investigated by torque and temperature curves given by the in-line Rheocord 9000 torque rheometer. Viscosity measurements, carried out in a Rapid Visco Analyser (RVA), and optical microscopy analysis were performed on the processed samples to complement the rheometry data. The results indicated that the water content and the rotation rate had a significant effect on the characteristics of the processed starch samples. For compositions with 10 and 20% (w/w) water contents and processed at 80 and 100rpm, degradation was observed at a larger extent. For compositions in which water had been added at a 30% (w/w) content, its plastifying property contributed to minimize degradation caused by mechanical and thermal inputs. In these cases, the granular structure of starch was largely preserved.