Effects of Boric Acid Ester Modified Magnesium Borate Whisker on the Mechanical Properties and Crystallization Kinetics of Polypropylene Composites.

Polypropylene (PP) is notch sensitive and brittle under severe conditions of deformation, limiting wider range of its usage as a structural load-bearing polymer. Hence, in this work the magnesium borate whisker (MBw), with similar mechanical properties to carbon fiber but much less expensive than polycrystalline silicon carbide, was modified by boric acid ester (BAE) and then used to fabricate PP composites. The mechanical properties, morphology, and non-isothermal crystallization property of virgin PP, PP/MBw, and PP/BAE-MBw composites were studied through mechanical testing, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC), respectively. The non-isothermal crystallization data was analyzed via Mo, Kissinger, and Dobreva methods. The results reveal that the incorporation of BAE-MBw into PP matrix results in higher tensile strength and impact strength than those of virgin PP and PP/MBw composite. The activation energies based on Kissinger were 190.20 kJ/mol for virgin PP, 206.59 kJ/mol for PP/MBw, and 218.98 kJ/mol for PP/BAE-MBw. The nucleation activities of whiskers determined by the Dobreva model were 0.86 for PP/MBw and 0.75 for PP/BAE-MBw. As a result, the whiskers, especially the modified whiskers, act as active substrates to facilitate heterogeneous nucleation, which leads to an increase in crystallization rate.

Experiences of interpersonal interaction among patients with chronic schizophrenia: A phenomenological study.

PURPOSE: To explore the subjective interpersonal interaction experiences of patients with chronic schizophrenia. DESIGN AND METHODS: Descriptive phenomenological, purposive sampling, in-depth one-to-one, and unstructured interviews were used. Colaizzi's method was used to analyze narratives. FINDINGS: Three themes and six subthemes were emerged: Feelings associated with interpersonal interactions (pleasant and unpleasant feelings experienced during interpersonal interactions); interpersonal interaction is a dynamic process (Positive and negative dynamic processes); selection of interaction targets (limitations in the selection of interaction targets and selection criteria for interaction targets). PRACTICE IMPLICATIONS: Professionals should understand the interpersonal interactions experiences of patients with schizophrenia to help them have a better interpersonal relationship.