Effect of Silica on the Mechanical Properties of Rubber Reclaim Composite

This study deals with preparation of rubber composite material, which is mainly used as sport floors, especially for kindergarten grounds. The selected material is reclaim rubber that is available at the state company for tire industry in Al-Najaf city Iraq. The reclaimed rubber (R) ( as a matrix) was mixed with different ratios of other rubber that is Styrene-Butadiene (SBR). It works as a bonding material.An additive which is cement kiln dust (CKD) was employed as a reinforcement phase. The ratios of the R to the SBR was as the following (100R), (95R+ 5SBR), (90R + 10SBR), (85R + 15SBR) and (80R + 20SBR). Different ratios of the CDK (10, 20, 30, 40, 50) pphr was added for each of the above mentioned batches. (80R + 20SBR + 40CDK) batch showed a promising behaviour and therefore was selected for furthers investigations. In order to improve its behaviour,SiO2 was introduced as a second additive.The silica was added to the selected batch with ratios of (5, 10, 15, 20) pphr. The best results are of the batch contains 15 pphrsilica. They reveal that the resilience was 62.2% before adding the SiO2, while it became52.2%after adding SiO2. In addition, the hardness was 62.5 Shore A without SiO2 and it has been62.3 ShoreAwith SiO2. The UV influence and thermal aging will be discussed in the following pages.