Flexible Packaging Meterials:Polystyrene and PVC After the First World War, improvements in chemical technology led to an explosion in new forms of plastics.  Among the earliest examples in the wave of new plastics were "polystyrene" (PS) and "polyvinyl chloride" (PVC), developed by the I.G. Farben company of Germany. Polystyrene is a rigid, brittle plastic that is now used to make plastic model kits, disposable eating utensils, and similar knickknacks.  It would also be the basis for one of the most popular "foamed" plastics, under the name "styrene foam" or "styrofoam."  Foam plastics can be synthesized in an "open cell" form, in which the foam bubbles are interconnected, as in an absorbent sponge, and "closed cell," in which all the bubbles are distinct, like tiny balloons, as in gas-filled foam insulation and floatation devices. PVC has side chains incorporating chlorine atoms, which form strong bonds.  PVC in its normal form is stiff, strong, heat and weather resistant, and is now used for making plumbing, gutters, house siding, enclosures for computers and other electronics gear, and compact-disk media.  PVC can also be softened with chemical processing, and in this form it is now used for shrink-wrap, food packaging, and raingear.

2011-12-17

Flexible Packaging Meterials:Nylon The real star of the plastics industry in the 1930s was "polyamide" (PA), far better known by its trade name "nylon."  Nylon was the first purely synthetic fiber, introduced by Du Pont Corporation at the 1939 World's Fair in New York City. In 1927, Du Pont had begun a secret development project designated "Fiber66," under the direction of a Harvard chemist named Wallace Carothers.  Carothers had been hired to perform pure research, and not only investigated new materials, but worked to understand their molecular structure and how it related to material properties.  He took some of the first steps on the road to "molecular design" of materials. His work led to the discovery of synthetic nylon fiber, which was very strong but also very flexible.  The first application was for bristles for toothbrushes.  However, Du Pont's real target was silk, particularly silk stockings. It took Du Pont twelve years and $27 million USD to refine nylon and develop the industrial processes for bulk manufacture.  With such a major investment, it was no surprise that Du Pont spared little expense to promote nylon after its introduction, creating a public sensation, or "nylon mania."  Nylon mania came to an abrupt stop at the end of 1941, when America entered World War II.  The production capacity that had been built up to produce nylon stockings, or just "nylons" for American women, was taken over to manufacture vast numbers of parachutes for fliers and paratroopers.  After the war ended, Du Pont went back to selling nylon to the public, engaging in another promotional campaign in 1946 that resulted in an even bigger craze triggering off "nylon riots." Nylon still remains an important plastic, and not just for use in fabrics.  In its bulk form, it is very wear-resistant, and so is    To assist recycling of disposable items, the Plastic Bottle Institute of the Society of the Plastics Industry devised the now-familiar scheme to mark plastic bottles by plastic type.  A recyclable plastic container using this scheme is marked with a triangle with three "chasing arrows" inside of it, which enclose a number giving the plastic type: PETE, HDPE, PVC, LDPE, PP, PS, and OTHER.

2011-12-17

Plastic Packaging Products Every day our lives are touched by plastic packaging products. These are some of the more common packaging products organized according to their plastic type.    PET (polyethylene terphthalate) beverage containers, food containers, boil-in food pouches, processed meat packages.    HDPE (high density polyethylene) milk bottles, cereal box liners, detergent bottles, oil bottles, margarine tubs, toys, plastic bags. PVC (polyvinyl chloride) food wrap, vegetable oil bottles, blister packaging. LDPE (low density polyethylene) shrink-wrap, plastic bags, garment bags, dry cleaning bags, squeezable food bottles.  PP (polypropylene) margarine and yogurt containers, caps for containers, wrapping to replace cellophane, medicine bottles.  PS (polystyrene) egg cartons, fast food trays, disposable plastic silverware, cups, compact disc jackets.

2011-12-17

China strengthens package recycling China’s central government proposes legislation to govern packaging, waste, recycling industries. If passed, legislation known as Method for Administration of Recycling Packaging Materials, will rank among toughest in world, according to report from PackWebasia.com, Singapore. Law based on “producer pays” principal requires brand owner to take back post consumer waste, impacts entire packaging supply chain. In addition, since export markets are not exempt, materials, such as styrene, which is to be banned, will not be permitted in any form of product packaging exported from China. Under draft law, all packaging must be recoverable, plus either recyclable or degradable. Packaging reduction, lightweighting becomes mandatory. Law also provides incentives for research in materials, technology; calls for establishment of waste recovery, recycling systems; regulates transport, storage of recyclable, recycled materials; categorizes materials, production processes as Encouraged, Restricted or Obsolete (banned); stipulates creation of inter-agency enforcement team, sliding scale of penalties. China’s New Packaging Legislation… report published by PackWebasia owner, EP Resources Pte. Ltd., provides annotated English translation of proposed law, Catalogue of Encouraged, Restricted and Obsolete Materials, sells for US$1,500.  

2011-12-17