Common problems of rubber compound

(1) The compounding agent agglomerates due to insufficient plasticization of raw rubber; The roll distance is too large; The roll temperature is too high, the glue loading capacity is too large, the powdered compounding agent contains coarse particles or agglomerates, too much gel, etc.

(2) The plasticity is too high, too low or uneven: the main reason is that the plasticity of plastic mixing is inappropriate; Mixing time is too long or too short; Improper mixing temperature; Add more or less plasticizer; More or less carbon black is added, or the wrong variety is used, and the mixing is uneven.

(3) The specific gravity is too large, too small or uneven, which is caused by inaccurate weighing of compounding agent; Mismatching or missing mixing, mismatching or addition in mixing. For example, when carbon black, zinc oxide and calcium carbonate are added more, or raw rubber and oil softeners are added less, the specific gravity will be too large. When the mixing is uneven, the specific gravity will be uneven.

(4) The hardness is too high, too low or uneven, mainly due to inaccurate weighing of vulcanizing agent, accelerator, reinforcing agent, raw rubber and softener, mismatching or missing matching, wrong addition or missing addition in mixing, etc. Uneven mixing results in uneven hardness.

(5) Frost spraying: the compounding agent sprays out the rubber surface to form a layer similar to "white frost". The main reason is that the dosage of some compounding agents is too large, which exceeds its solubility in rubber at room temperature. Frost spraying will also be caused by insufficient mixing of raw rubber, uneven mixing and high mixing temperature.