Blends of polyblend and bitumen, when used, help to increase road life by a factor of three . What is the reason?

Explanation

Polyblend is a power of recycled modified plastic. The binding property of plastic makes the road last longer besides giving added strength to withstand more loads. This is because
(i) Plastic increases the melting point of the bitumen which would prevent it from melting in india's hot and extremely humid climate , where temperature frequently cross `50^(@)`C .
(ii) Rainwater will not seep through because of the plastic in the tar.