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This work deals with polycaprolactone/babassu compounds having two types of filler, derived from the fruit of the babassu palm. PCL compounds with 10%, 20%, and 30% of epicarp and mesocarp of babassu were prepared in an internal laboratory mixer and their morphology, rheological characteristics, and thermal properties, were determined as a function of the type and content of the load. Melt viscosity increases with filler incorporation and loading levels, and at the same loading level the viscosity of epicarp compounds is higher. Rheological analysis indicates that PCL melts behave as Newtonian liquids while subjected to shear rates in the range 10–100 s−1. DSC data shows babassu promotes PCL melt crystallization, shifting crystallization peak to higher temperatures and increasing crystallization rate. Crystallinity increases steadily with filler content and shows a weak dependence on filler type. Optical microscopy shows higher particle size and particle agglomeration at higher filler contents. SEM analysis shows poor adhesion polymer/filler interface. Small round particles, perceived as background in the images were attributed to the presence of starch granules. POLYM. COMPOS., 40:E540–E549, 2019. © 2018 Society of Plastics Engineers

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The slow degradation and the high environmental impact caused by inappropriate disposal of polymer products are the main factors prompting scientists to either substitute conventional polymers by biodegradable ones or to enhance biodegradation of short-lived polymer products, particularly those used in packaging. Polymer blends of conventional and biodegradable polymers is one of the alternative solutions found to improve mechanical properties and accelerate polymer degradation after disposal. This work investigates the effect of incorporating different metallic stearates (Zn and Mg) on the rheological, thermal and mechanical characteristics of 75PBAT/25PCL blends processed in an internal laboratory mixer. The results of torque rheometry suggest degradation during processing potentialized with the stearates incorporation, while that of DSC indicated that the crystallinity of the blends increased with the incorporation of additives. TG data showed a reduction in the thermal stability of the systems containing stearates. Incorporation of stearates resulted in strongly thermally degraded systems. Adding up to 0.25% of magnesium stearate to the blend 75PBAT/25PCL leads to a material that combines maintenance or improvement of properties combined with higher decomposition.

Poly(lactic acid) (PLA) is one of the most important ecological thermoplastics due to its good mechanical properties. In light of this, investigations related to the effects of PLA processing parameters are important as they affect the final product performance. This work aimed to determine the viscosity-temperature coefficient (β) and pseudoplastic index (n) of PLA and estimate its degradation rate during processing using an internal mixer. The viscosity coefficient was determined applying different processing temperatures at the same rotors rotation rate, which allowed estimating β = 0.048 ◦C−1. PLA’s pseudoplastic index (n) under the tested conditions suggested a value of approximately 0.71. PLA’s degradation rate was around 4% under rotor rate of 120 rpm and temperature of 190 ◦C.

Revisão Sistemática com metanálise, até dezembro de 2020. Objetivo comparar incidência de erros de prescrição antes e após introdução de Sistemas de Prescrição Eletrônica associados ou não a Sistemas de Apoio à Decisão em diferentes settings pediátricos. Em dez estudos em UTI a redução em erros de dosagem (um tipo de erro de prescrição) variou de 15% a 30%. Dois estudos com supressão total de erros. Em enfermaria as reduções foram de 36%, 45%, 67% e 74%. A redução foi de 7,4 de erros gerais de prescrição. Evidenciou-se redução de risco de erros de dosagem em pediatria com o uso de sistemas de prescrição eletrônica para UTI, enfermaria e ambulatório.

The packaging industry requires materials capable of offering barriers to the entry of microorganisms, with the ability to protect and maintain the characteristics of the packaging content. The use of fillers can enhance these barrier properties to the polymeric material. This work investigates the effect of incorporating different fillers (organophilic clay and corn straw) on the rheological, thermal, mechanical and permeability characteristics of polycaprolactone (PCL) processed in an internal laboratory mixer. The results of torque rheometry suggest polymer matrix degradation during processing did not increase, nor the thermal stability of the matrix. Composite films showed higher tensile strength, higher stiffness and lower elongation. Incorporation of the fillers in the PCL matrix reduced the permeability to oxygen and carbon dioxide gases of the produced films. Adding up to 1% of organoclay C20A or corn straw to PCL leads to a material that combines maintenance or improvement of properties combined with lower permeability to oxygen and carbon dioxide, which confirms the potential use of these systems in packaging industry.