Diatomite and silica were mechanically blended with natural rubber (NR)/dissolved styrene butadiene rubber (SSBR) to prepare composite materials. The process

dynamic properties and mechanical properties of the composites were studied

and the fracture morphology of the composites was observed by SEM. The results showed that with the increase of diatomite content

the vulcanization time of the composites decreased

the Mooney viscosity and the Payne effect increased

the loss factor increased too

while the mechanical properties decreased; but the scorch time and the loss factor at 60 ℃ were changed little. When the dosage of diatomite was 20 phr

the agglomeration and gelation of silica were reduced

the Payne effect of the composite was weaker and the microstructure was uniform;When the dosage of diatomite was 10~20 phr

the tensile strength and modulus were higher. When the dosage of diatomite was 30 phr

the loss factor of the composite at 0 ℃ was larger.