Heavy-Duty Shipping Sacks Another packaging application finding more demand in Asia Pacific is heavy duty shipping sacks (HDSS). HDSS packaging is typically designed to contain more than 20kg of granular goods (e.g. polymer resins, solid chemicals, cement, animal feeds, rice and similar goods). Incumbent HDSS material structures currently range from polypropylene raffia, paper/ plastic lamination to pure polyolefin based co-extrusion film. Many users are seeking to downsize their structures while maintaining the performances, and Dow has formulated differentiated polyethylene-based solutions with the use of higher alpha olefin-based polyethylene resins.