1 gallon bucket is used for rotomoulding, and the material used in such a process is generally pulverized into a powder which is melted and flows in a thermal cycle during operation. Rotational molding uses two types of PE: generic and crosslinkable. General-purpose MDPE/HDPE typically have densities ranging from 0.935 to 0.945 g/cc and have a narrow MWD for high impact and low warpage, with melt indices typically ranging from 3-8. Higher MI grades are generally not applicable because they do not have the desired impact and environmental stress crack resistance of the rotomoulded article.
The 1 gallon barrel high performance rotational molding application utilizes the unique properties of its chemically crosslinkable grade. These grades are fluid in the first stage of the molding cycle and then cross-linked to form their excellent resistance to environmental stress cracking and toughness. Abrasion resistance and weather resistance. Crosslinkable PEs are suitable for large containers ranging from 500-gal to various chemical storage tanks to 20,000-gal agricultural storage tanks.
1 gallon barrel processing is generally done by ordinary blown film processing or flat extrusion processing. Most PEs are used for film, general low density PE (LDPE) or linear low density PE (LLDPE).
HDPE film grades are generally used where superior stretchability and excellent barrier properties are required. For example, HDPE films are commonly used in commodity bags, grocery bags, and food packaging.