Commercial filled polypropylene compounds

Effect of talc volume fraction on the flexural and elasticity moduli of commercial filled polypropylene compounds clear squares are average moduli data gray shaded diamonds are data from one selected manufacturer the dotted curve was calculated with the Guth and Gold equation and = 1.152 GPa and 1.191 GPa for the flexural and elasticity moduli respectively the solid curve was calculated with the modified equation and an anisometry factor/ = 2.1. 

Effect of talc volume fraction on the impact resistance of commercial filled polypropylene compounds clear squares are average moduli data shaded diamonds are data from one selected... 

All commercial polymers are compounds that have additives primarily intended as stabilizers. These additives protect the polymer from oxygen, heat, and other aspects of the environment. Many available polymer products are compounds that involve a wide range of ingredients, including commercial products such as polypropylene-based thermoplastic elastomers, polyvinyl chloride pipes, mineral-filled polypropylene, and pneumatic tire components. These compounds contain not only stabilizers but also other polymers, fillers, oils, curatives, accelerators (for curatives), and other ingredients. 

Worldwide, ready-to-be-processed CaCOg filled polymers are available from a number of compounders. Polypropylene compounds, in the 10-40%wt range are available from numerous producers and grades up to 50%wt are also locally offered for special applications. Table 6.8 gives the average properties of typical commercial PP-CaCOg composites, as compiled from manufacturers data sheets (when available). 

Surface treatment of caldte with stearic acid significantly reduces the viscosities and yield values of molten polymer compounds [4,5]. Small CaCOj particles are commercially treated with stearic add to improve their processability. Suetsugu and White [5] have investigated stearic acid effects on a calcite-filled system. They found an increasing order of reduction with decreasing particle size and decreasing shear rate. K. J. Kim and White studied the effect of stearic add on caldte and on talc particles in a polypropylene (PP) matrix [9 to 11 ]. 

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