The effect of molecular weight on the melting point of polyethylene is quite significant. Polyethylene is a polymer, which means it consists of long chains of ethylene monomers C2H4 linked together. The molecular weight of polyethylene is determined by the number of monomers in the chain, and it can vary widely depending on the specific type of polyethylene.As the molecular weight of polyethylene increases, the melting point of the polymer also increases. This is because higher molecular weight polymers have longer chains, which leads to stronger intermolecular forces, such as van der Waals forces, between the chains. These stronger forces require more energy to overcome, resulting in a higher melting point.In general, low-density polyethylene LDPE has a lower molecular weight and a lower melting point around 105-115C compared to high-density polyethylene HDPE , which has a higher molecular weight and a higher melting point around 130-137C .It is important to note that other factors, such as the degree of crystallinity, branching, and cross-linking, can also influence the melting point of polyethylene. However, molecular weight remains a significant factor in determining the melting point of this polymer.