Overview of the Cast Polyolefin Film Extrusion Technology for Multi-Layer Packaging Applications

Abstract

The review article presents the technology of producing polyolefin-based films by extrusion casting. Due to the wide use of this type of film as packaging for food and other goods, obtaining films with favorable properties is still a challenge for many groups of producers in the plastics market. The feedblock process and multimanifold process are the main methods of producing multi-layer film. In the case of food films, appropriate barrier properties are required, as well as durability and puncture resistance also at low temperatures. On the other hand, in order to properly pack and present products, an appropriate degree of transparency must be maintained. Therefore, processing aids such as anti-slip, anti-block and release agents are commonly used. Other popular modifiers, such as waxes, fatty acid amides and mineral fillers—silica, talc or calcium carbonate–and their use in film extrusion are discussed. The article also presents common production problems and their prevention.

Flow-Induced Polymer Crystallization under Pressure and Its Engineering Application in “Structuring” Polymer Processing

“…Here, we focus on the "structuring" polymer processing based on injection molding. Other "structuring" polymer processing methods have been reviewed by Peterlin 123 and An et al 124 on extrusion, Fu et al 125 and Dziadowiec et al 126 on film casting, and Xu et al 127 and Hufenus et al 128 on melt spinning. Based on conventional injection molding (CIM), a novel type of injection molding has been developed, which introduces a distinct melt flow feature during injection molding usually in the packing stage; i.e., the melt flow in the cavity of mold is manipulated by using pressure-driven flow.…”

Recent developments in 3D-printed membranes for water desalination

“…If different types of polymers, or polymers with various colorants and additives, are extruded into a single film, multiple extruders can be fed into one die. Cast film extrusion finds extensive application in producing polypropylene (PP) films for packaging purposes [44][45][46]. Additionally, extrusion is commonly employed in manufacturing polytetrafluoroethylene and other fluorinated polymer membranes.…”

Mechanical, Rheological, and Heat Seal Properties of 1‐Octene Grafted Low Density Polyethylene Films

“…According to literature review, grafting side branches in the form of hydrocarbon or functional groups to the polymer chain of polyolefins has a direct effect on the adhesion strength of these materials. [ 13 ] The results indicated that the structural factors which affect the heat sealing of polymers are the possibility of penetration of polymer chains into the interface of two polymeric surfaces in contact with each other, the possibility of chemical reaction between chains, and the possibility of crystallization. Meanwhile, the use of the reactive melt mixing method and the possibility of chemical reactions occurring during the forming process in the molten state, taking into account the major advantages such as economic efficiency and the possibility of industrialization, the ease of carrying out the process, and high efficiency, the importance of using this method as an alternative other methods are noted.…”