Hello Aspirant, Plastic technology is a specialized branch of study which includes the study of diverse types of chemicals that exhibits plasticity. It also involves the study of several methods in which plastics can be utilized for use in human life. The field is also concerned with the research works to produce plastics eco friendly. 

The pay package is higher in the private sector, around Rs. 9000 - 12,000 per month. And it is also depend on your knowledge and skill. 

I hope this will help you.