Effective Strategy for the Production of Novel Magnetite Poly(vinyl chloride) Nanocomposite Films With Iron Oxide Nanoparticles Double-Capped Through Citric Acid and Vitamin C Shadpour Mallakpour, 1,2,3 Mashal Javadpour 1 1 Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran 2 Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran 3 Center of Excellence in Sensors and Green Chemistry, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran This study focuses on the synthesis of iron oxide (Fe 3 O 4 ) nanoparticles (NPs), modification of NPs with organic molecules of citric acid (CA) and ascorbic acid (AS), and the incorporation of modified magnetic NPs into poly(vinyl chloride) (PVC) matrix. Biodegradable CA and AS coupling agents can improve the organic func- tional groups on the surface of Fe 3 O 4 NPs. Magnetic PVC/Fe 3 O 4 , CA, and AS nanocomposite (NC) films con- taining 4, 8, and 12 wt% of NPs were successfully man- ufactured by a fast, green, and safe strategy under ultrasonic irradiation to improve interfacial interactions and dispersion of modified NPs in the polymeric matrix. The surface functionality group’s effect on the proper- ties and also on morphology of modified NPs and NCs were analyzed by Fourier-transform infrared spectros- copy, thermogravimetric analysis, ultraviolet-visible absorption spectroscopy, X-ray diffraction, field emis- sion scanning electron microscopy, and transmission electron microscopy. Thermogravimetric analysis indi- cated that the thermal stability of the NCs was not destroyed in comparison with the PVC polymer. It was found that modified Fe 3 O 4 NPs have elevated the flame- retardancy of the PVC hybrids. In addition, the surface morphology images showed that NPs were dispersed homogenously into the polymer matrix at nanoscale. J. VINYL ADDIT. TECHNOL., 00:000–000, 2015. V C 2015 Society of Plastics Engineers INTRODUCTION During the last decade, the development of (magneto- polymer)-containing ferromagnetic nanoparticles (NPs) has been the source of a spectacular new phenomenon because of their magnetic behavior and potential applica- tions (for example, magnetic drug targeting, molecular and cell recognition, and separation) [1, 2]. Poly(vinyl chloride) (PVC), an odorless and solid plas- tic, is made up of many vinyl chloride molecules that are linked together to form a polymer (C 2 H 3 Cl) n . PVC, a nor- mal impact and high corrosion-resistant polymer, is ideally suited for applications where maximum chemical resistance is necessary. Its high strength-to-weight ratio, low cost, ease of fabrication, and economic balance make it the material of choice. PVC is a versatile thermoplastic material used to make pipes, vinyl flooring, wire and cable coatings, packaging materials, door and window frames, paper and textile finishes, thin sheeting, roof membranes, containers, and automotive parts. When soft- ened with phthalates, PVC is used to make some medical devices, including blood bags, feeding tubes, catheters, and parts of dialysis devices. Consumer products made with PVC include cloths, shades, furniture, carpet back- ing, and credit cards [3–5]. Citric acid (CA), a weak organic acid and natural pre- servative, is used to add a sour taste to foods and soft drinks. It also serves as an environmentally benign clean- ing agent and acts as an antioxidant, calculi dissolution agent, and anticoagulant. The antimicrobial activities of this food preservative have been observed against bacteria without effect on food [6, 7]. Ascorbic acid (AS), a water-soluble micronutrient, is the reduced form of vitamin C. AS is a required compo- nent of the human diet because of its multiple biological functions. Small amounts of vitamin C as a potent reduc- ing agent and scavenger of free radicals can prevent the deficiency disease, scurvy; also, vitamin C may protect against oxidative damage and limit inflammation [8, 9]. Correspondence to: Shadpour Mallakpour; e-mail: mallak@cc.iut.ac.ir DOI 10.1002/vnl.21509 Published online in Wiley Online Library (wileyonlinelibrary.com). V C 2015 Society of Plastics Engineers JOURNAL OF VINYL & ADDITIVE TECHNOLOGY—2015