Effect of recycled polypropylene on polypropylene/high‐density polyethylene blends

Abstract

ABSTRACT:The effect of recycled PP on incompatible blends of virgin polypropylene (PP) and high-density polyethylene (HDPE) was studied. Recycled PP from urban solid waste was extracted with methyl ethyl ketone and the compatibilizing action of the product before and after extraction was examined. The characterization of the recycled PP was performed by FTIR, NMR, and DSC analyses. Mechanical properties of the blends were evaluated. The results showed partial compatibility of the blend components, reflected in the improvement of the tensile strength and elongation. Best results were achieved by the addition of extracted recycled PP on the 50/50 PP/HDPE blends.

Análisis multivariado de parámetros fisicoquímicos del relleno sanitario de São Giacomo de Caxias do Sul, RS en la de degradaciòn de polipropilene

“…La energía absorbida por la influencia del calor, luz, etc estrés mecánico, la rotura causa de enlaces CH de los servicios de carbono, que tienen vínculos más débiles que los otros carbones, lo que genera radicales libres que son capaces de reaccionar con el oxígeno para formar peróxidos e hidroperóxidos, que a su vez producen más radicales libres resultantes de la división de cadenas [19][20][21][22] . El PP puede presentar varios grupos cromóforos (grupos generadores de radicales libres) como iniciadores de la degradación del PP que inducen a la ruptura de la cadena.…”

Recycling Polymer Blends

“…In this case the properties of the recycled blends are suitable to applications requiring good mechanical performances, but, of course, the costs of the operation are higher. Actually, an attempt was made (Bonelli et al 2001) to compatibilize the blend with r-PP extracted by floatation. It was found that PP exposed to random/noncontrolled outdoor conditions provided spontaneous non-oxidative chemical modifications that brought a certain compatibilization action to the PE/PP blends.…”

Heat transfer enhancement for the power-law fluids through a parallel-plate double-pass heat exchangers with external recycle

“…The resultant governing equations obtained by theoretical treatments of such conjugated Graetz problems could be solved analytically by means of orthogonal expansion techniques [11,12]. The heat transfer enhancement in one or more flowing streams has attracted a great deal of interest in recent years because of the wide use of recycle effect in chemical processes and food industries such as distillation [13], extraction [14], adsorption [15], mass diffusion [16], thermal diffusion [17], loop reactors [18], air-lift reactor [19] and draft-tube bubble column [20].…”