Abstract
Vapor Phase Corrosion Inhibitors (VCIs) are used for safe and cost-effective protection of a wide range of metal articles. One large market includes packaging materials for storage and transportation of metal parts. Plastic packaging films can be readily impregnated with VCIs to provide corrosion protection, in addition to the basic physical barrier (against water, dirt, vapors) afforded by the plastic. Generally, VCI containing plastic films are recyclable. Likewise, they can be made from recycled plastics. However, when manufacturing with commercially available recycle streams, use of the recycled plastic is often limited by contamination and extent of polymer degradation.
This paper will discuss the benefits of using in-house recycling lines; including improved environmental profile, better quality, and cost saving. The results are supported by data and experience with in-house recycling lines at two production facilities.
Introduction
Vapor Phase Corrosion Inhibitors (VCIs) are a well-known and highly versatile range of products for the prevention of corrosion.1 VCIs can be delivered to the target metal in a variety of ways. One common product is plastic packaging. 2 Plastic VCI films are a versatile and highly effective article for protection of items from corrosion. They are generally made from polyethylene, which is readily available, cost effective, and usually recyclable. 3 Production of VCI films usually results in the production of at least some “Scrap” film. This may be film of variable size produced during production start-up, or film that does not meet specifications. Scrap can be disposed as trash, but is preferably recycled. The usual mode of recycling is to reprocess it (melt processing) into pellets which can be re-used in production of new film. 3 It is often referred to as “Repro”. Reprocessing can be done in-house with dedicated machines or the scrap can be sent to external facilities that specialize in recycling. The quality of Repro can vary considerably with the quality/purity of the scrap and the conditions used for reprocessing (particularly temperature and shear). 4 In this paper, we report on studies varying the source and quantity of Repro and the effects on product quality. Results and commercial implications are discussed.
