Most of a dragonfly's life is spent in the larval stage where it molts from six to fifteen times. Depending on altitude and latitude, larval development varies from the common one or two years to as many as six years.
HOME. OPS (Biaxially Oriented Polystyrene Sheet) is a thermoformable sheet produced by stretching polystyrene in two directions, lengthwise and crosswise. OPS can be used widely for transparent containers such as lids, trays, and foldable food containers because it has high transparency, rigidity and hygiene.Manufacturing Process of OPS Applications of OPS Most of OPS are used for food packaging containers such as food packs, trays, lids and fruit containers.PS can be used widely for transparent containers such as lids, trays, and foldable food containers because it has high transparency, rigidity and hygiene. Manufacturing Process of OPS Applications of OPS Most of OPS are used for food packaging containers such as food packs, trays, lids and fruit containers.
Most commercial polypropylene is isotactic and has an intermediate level of crystallinity between that of low-density polyethylene (LDPE) and high-density polyethylene (HDPE). Polypropylene is normally tough and flexible, especially when copolymerized with ethylene.hen the methyl groups in a polypropylene chain exhibit no preferred orientation, the polymers are called atactic. Atactic polypropylene is an amorphous rubbery material. It can be produced commercially either with a special type of supported Ziegler-Natta catalyst or with some metallocene catalysts.