Fusion bonding of maleated polyethylene blends to polyamide 6

Abstract

Blends of linear low‐density polyethylene (LLDPE) and linear low‐density polyethylene–grafted maleic anhydride (LLDPE‐gMA) were used to promote the adhesion to polyamide 6 (PA) in a three‐layer coextruded film without using an additional adhesive or tie layer. The effect of bonding time and molecular weight (MW) of different maleated polyethylenes on the peel strength of the joints was analyzed. Direct evidence of a copolymer formed in‐situ at the interfaces is also considered. The peel strength of fusion bonded layers of LLDPE/LLDPE‐gMA blends with PA strongly depends on bonding time and molecular weight of the maleated polymer. Tensile properties of three‐layer films, made up of PA as the central layer and LLDPE/LLDPE‐gMA blends as the two external layers, are improved with increases in the maleic anhydride (MA) content in the blend. The in‐situ formation of a copolymer between the MA in the blend and the terminal amine groups of the PA was confirmed by the Molau test, infrared (IR) spectroscopy, and thermal analysis (DSC).

Compatibilization of polyethylene/polyaniline blends with polyethylene‐graft‐maleic anhydride

“…The effect of the incorporation of polyethylene‐ graft ‐maleic anhydride (PEgMA) into blends of LDPE and PANIDBSA prepared by extrusion is evaluated. A maleic anhydride grafted polymer was considered for this investigation on the basis of its wide use as a compatibilizer in binary immiscible blends 14–17. The interactions between the constituents of the composite were analyzed with Fourier transform infrared (FTIR) spectroscopic measurements, ultraviolet–visible (UV–vis)/near‐infrared (NIR) spectroscopy, and dynamic mechanical analysis (DMA).…”

Reactive compatibilizer precursors for LDPE/PA6 blends, 1

“…The possibility of compounding polyolefins with polar polymers such as polyesters and polyamides to produce multilayer colaminates, blow‐molded blends with laminar morphology or conventional blends for applications such as food‐packaging films, water‐ and hydrocarbon‐proof containers, impact modified materials, etc., has been investigated extensively in recent years 1–4. Among these new combinations, those based on polyethylene (PE) and polyamide‐6 (PA) have been the subject of particular attention because of the advantages expected from a synergistic match of the low price, good processability and excellent impact properties of the former resin with the thermal and mechanical properties and oil resistance of the latter 5–7.…”

“…Compatibilization of polymer blends by reactions taking place during compounding is becoming increasingly important9,10 and a range of chemistries has been used to realize it 11–13. Thus, the preparation of several high molar mass CPs consisting of polyolefin chains with reactive functional groups, such as anhydride, epoxy, isocyanate, oxazoline, glycidylmethacrylate, etc., and their use for the reactive compatibilization of polyolefin/polyamide blends have been described 1–3,5,6,14–46. All these CPs have been shown to lower the interfacial tension, improve the minor phase dispersion, enhance the adhesion of the phases, hinder the droplet coalescence and to enhance the mechanical properties of the blends.…”

Surface analysis of aminated polypropylene films as an adhesion promoter to polycarbonate film

“…Modification of polyolefins (POs) by grafting of maleic anhydride, acrylic acid, or methacrylic acid monomers has been used to obtain reactive polymers with acidic functionality 6–8. These reactive sites have been used as compatibilizing agents between polyolefins and polar polymers such as polyamides9, 10 and polyesters 11, 12. However, there is a growing interest in preparing polymers containing amine groups, specifically in polyolefins.…”