Qualitative and quantitative responses of recycled polyolefinic blend morphology and mechanical properties as a unction of polymer component ratio, compatibilizer concentration, and mixing parameters were investigated using response surface methodology. Phase contrast optical microscopy (PCOM) and scanning electron microscopy (SEM) were used to characterize blend micromorphological phase structures for both dispersed and co-continuous mixtures of HDPE in PP. Full polynomial models up to order 2(y = a0 + a1x1 + a2x2 + a3x3 + a11x1(2) + a22x2(2) a33x3(2) + a12x1x2 + a13x1x3 + a23x2x3) were generated for each response as a function of the input factors using multiple linear regression (MLR). Optimization techniques were used to develop both processability windows and optimum blend conversions costs for a given balance of properties.