Thermo‐physical properties of polypropylene fibers containing a microencapsulated flame retardant

Abstract

A microencapsulated flame retardant with a melamine‐formaldehyde shell was prepared by in situ polymerization, then incorporated into an iPP matrix with a coupling agent to manufacture multifilament yarns by melt spinning. The influence of the post‐treatment on the resulted microcapsules with an alcoholic solution was also studied. The spinnability of these formulations based on the interface characterization from contact angle measurements, tensile test and thermal characterizations was explored to determine the maximum draw ratio (DR) to apply. Finally, knitted fabrics were processed from multifilaments, and their flame‐retardant properties were evaluated by performing fire tests according to the FMVSS 302 and Din 4102 part B experiments. The different mechanical and thermal behaviors were discussed in terms of the influence of the DR and the post‐treatment applied on fibers during the spinning process and during the recovery of the microcapsules, respectively. The results showed that it was possible to obtain multifilament yarns with a DR of 4, but the best properties were obtained with a DR of 3 and for un‐treated microcapsules. Furthermore, the samples containing un‐treated microcapsules reach a B rating at the FMVSS test with a fast flame progression and a very low duration of burning. Copyright © 2012 John Wiley & Sons, Ltd.

Melt-spun polypropylene filaments containing paraffin microcapsules for multifunctional hybrid yarns and smart thermoregulating thermoplastic composites

“…Even though there are several examples in the literature of polymer fibers containing PCM microcapsules [43][44][45][46][47][48], the process has been studied only to meet the requirements of the textile industry, and not to produce hybrid yarns for thermoplastic laminates. This investigation would be interesting in order to produce multifunctional hybrid yarns containing not only a PCM, but also other microencapsulated functional fillers such as self-healing, antimicrobial, and fire-retardant agents [49,50]. The aim of the present work is to develop and characterize polymer fibers containing paraffin microcapsules for a subsequent realization of a PCM-enhanced thermoplastic laminate, which, to the best of the authors' knowledge, has never been investigated in the open scientific literature.…”

Sol–gel microencapsulation of oil phase with Pickering and nonionic surfactant based emulsions

“…Indeed, sol-gel encapsulation of this highly viscous colorless fluid improves polyethylene terephthalate thermal behavior and displays good flame retardancy for charring polymers as polycarbonates. [3,19].…”

“…Regardless the impregnation process, capsules need to have sufficient mechanical properties to resist to stress during utilization. Silica shells or matrices are frequently used to encapsulate various types of active agents such as dyes [7], drugs [8], enzymes [9], bacteria [10] or fire retardant [3], and are widely used in cosmetics formulation because of their biocompatibility and limited toxicity [11]. Moreover, they exhibit high mechanical properties [12], excellent chemical and thermal stabilities with limited release of toxic gases during decomposition.…”

Potential use of microcapsules in manufacture of fibrous products: A review

“…Today, microcapsules are present in the market as interesting niche, with the potential for further development of modern fibrous products. The microcapsules can be used as skin care materials, scenting, insect repellents, sensors, flame‐resistant products, antibacterial materials . Therefore, the main positive feature of microencapsulation is that this process can be applied as one of the quality preservation techniques of sensitive substances and as method for production of advanced materials with new valuable properties .…”