Alexander B. Morgan

Flame retardant polymer nanocomposites

Preface. Acronyms. 1 Introduction to Flame Retardancy and Polymer Flammability (Sergei V. Levchik). 1.1 Introduction. 1.2 Polymer Combustion and Testing. 1.3 Flame Retardancy. 1.4 Conclusions and Future Outlook. References. 2 Fundamentals of Polymer Nanocomposite Technology (E. Manias, G. Polizos, H. Nakajima, and M. J. Heidecker). 2.1 Introduction. 2.2 Fundamentals of Polymer Nanocomposites. 2.3 Effects of Nanofillers on Material Properties. 2.4 Future Outlook. References. 3 Flame Retardant Mechanism of Polymer-Clay Nanocomposites (Jeffrey W. Gilman). 3.1 Introduction. 3.2 Flame Retardant Mechanism. 3.3 Conclusions and Future Outlook. References. 4 Molecular Mechanics Calculations of the Thermodynamic Stabilities of Polymer-Carbon Nanotube Composites (Stanislav I. Stoliarov and Marc R. Nyden). 4.1 Introduction. 4.2 Background and Context. 4.3 Description of the Method. 4.4 Application to PS-CNT Composites. 4.5 Uncertainties and Limitations. 4.6 Summary and Conclusions. References. 5 Considerations Regarding Specific Impacts of the Principal Fire Retardancy Mechanisms in Nanocomposites (Bernhard Schartel). 5.1 Introduction. 5.2 Influence of Nanostructured Morphology. 5.3 Fire Retardancy Effects and Their Impact on the Fire Behavior of Nanocomposites. 5.4 Assessment of Fire Retardancy. 5.5 Summary and Conclusions. References. 6 Intumescence and Nanocomposites: a Novel Route for Flame-Retarding Polymeric Materials (Serge Bourbigot and Sophie Duquesne). 6.1 Introduction. 6.2 Basics of Intumescence. 6.3 Zeolites as Synergistic Agents in Intumescent Systems. 6.4 Intumescents in Polymer Nanocomposites. 6.5 Nanofillers as Synergists in Intumescent Systems. 6.6 Critical Overview of Recent Advances. 6.7 Summary and Conclusion. References. 7 Flame Retardant Properties of Organoclays and Carbon Nanotubes and Their Combinations with Alumina Trihydrate (Gunter Beyer). 7.1 Introduction. 7.2 Experimental Process. 7.3 Organoclay Nanocomposites. 7.4 Carbon Nanotube Nanocomposites. 7.5 Summary and Conclusions. References. 8 Nanocomposites with Halogen and Nonintumescent Phosphorus Flame Retardant Additives (Yuan Hu and Lei Song). 8.1 Introduction. 8.2 Preparation Methods and Morphological Study. 8.3 Thermal Stability. 8.4 Mechanical Properties. 8.5 Flammability Properties. 8.6 Flame Retardant Mechanism. 8.7 Summary and Conclusions. References. 9 Thermoset Fire Retardant Nanocomposites (Mauro Zammarano). 9.1 Introduction. 9.2 Clays. 9.3 Thermoset Nanocomposites. 9.4 Epoxy Nanocomposites Based on Cationic Clays. 9.5 Epoxy Nanocomposites Based on Anionic Clays. 9.6 Polyurethane Nanocomposites. 9.7 Vinyl Ester Nanocomposites. 9.8 Summary and Conclusions. References. 10 Progress in Flammability Studies of Nanocomposites with New Types of Nanoparticles (Takashi Kashiwagi). 10.1 Introduction. 10.2 Nanoscale Oxide-Based Nanocomposites. 10.3 Carbon-Based Nanocomposites. 10.4 Discussion of Results. 10.5 Summary and Conclusions. References. 11 Potential Applications of Nanocomposites for Flame Retardancy (A. Richard Horrocks and Baljinder K. Kandola). 11.1 Introduction. 11.2 Requirements for Nanocomposite System Applications. 11.3 Potential Application Areas. 11.4 Future Outlook. References. 12 Practical Issues and Future Trends in Polymer Nanocomposite Flammability Research (Alexander B. Morgan and Charles A. Wilkie). 12.1 Introduction. 12.2 Polymer Nanocomposite Structure and Dispersion. 12.3 Polymer Nanocomposite Analysis. 12.4 Changing Fire and Environmental Regulations. 12.5 Current Environmental Health and Safety Status for Nanoparticles. 12.6 Commercialization Hurdles. 12.7 Fundamentals of Polymer Nanocomposite Flammability. 12.8 Future Outlook. References. Index.

Intumescent All‐Polymer Multilayer Nanocoating Capable of Extinguishing Flame on Fabric

According to the National Fire Protection Association (NFPA), there were an estimated 1.3 million fi res in the United States in 2009, which resulted in 3010 civilian deaths (one every 175 minutes), 17 050 injuries (one every 31 minutes), [ 1 ] and direct property loss estimated at

Graphite Oxide Flame-Retardant Polymer Nanocomposites

12.5 billion. There were more than 40 000 deaths worldwide from fi re in 2006 and it cost every country an average of 1% of their gross domestic product in property loss, medical services for burn victims, etc. [ 2 ] Firerelated issues continue to drive the development of materials that can reduce fi re risk to save lives and protect property, but any fl ame retardants used to reduce that fi re risk have to meet various safety standards to reduce the deleterious effect on the environment or human health. Textiles in particular require effective anti-fl ammable performance combined with minimal enviornmental impact because they are often washed and fl ame retardant additives can leach out of the fabric and into the environment. [ 3 , 4 ] There are numerous strategies used to make textile fi bers fl ame retardant: surface treatment, fi re-retardant additives or co-monomers in synthetic fi bers, nanocomposite technology, heat-resistant and inherently fi re-retardant fi bers, and fi ber blending. [ 5 ] More recently, layer-by-layer (LbL) assembly has been used as a surface treatment to impart fl ame resistance to cotton fabric by coating each individual fi ber with a claypolymer nanobrick wall. [ 6 ]

Intumescent Multilayer Nanocoating, Made with Renewable Polyelectrolytes, for Flame-Retardant Cotton

Graphite oxide (GO) polymer nanocomposites were developed at 1, 5, and 10 wt % GO with polycarbonate (PC), acrylonitrile butadiene styrene, and high-impact polystyrene for the purpose of evaluating the flammability reduction and material properties of the resulting systems. The overall morphology and dispersion of GO within the polymer nanocomposites were studied by scanning electron microscopy and optical microscopy; GO was found to be well-dispersed throughout the matrix without the formation of large aggregates. Mechanical testing was performed using dynamic mechanical analysis to measure the storage modulus, which increased for all polymer systems with increased GO loading. Microscale oxygen consumption calorimetry revealed that the addition of GO reduced the total heat release and peak heat release rates in all systems, and GO-PC composites demonstrated very fast self-extinguishing times in vertical open flame tests, which are important to some regulatory fire safety applications.

Effects of organoclay Soxhlet extraction on mechanical properties, flammability properties and organoclay dispersion of polypropylene nanocomposites

Thin films of fully renewable and environmentally benign electrolytes, cationic chitosan (CH) and anionic phytic acid (PA), were deposited on cotton fabric via layer-by-layer (LbL) assembly in an effort to reduce flammability. Altering the pH of aqueous deposition solutions modifies the composition of the final nanocoating. CH-PA films created at pH 6 were thicker and had 48 wt % PA in the coating, while the thinnest films (with a PA content of 66 wt %) were created at pH 4. Each coating was evaluated at both 30 bilayers (BL) and at the same coating weight added to the fabric. In a vertical flame test, fabrics coated with high PA content multilayers completely extinguished the flame, while uncoated cotton was completely consumed. Microcombustion calorimetry confirmed that all coated fabric reduces peak heat release rate (pkHRR) by at least 50% relative to the uncoated control. Fabric coated with pH 4 solutions shows the greatest reduction in pkHRR and total heat release of 60% and 76%, respectively. This superior performance is believed to be due to high phosphorus content that enhances the intumescent behavior of these nanocoatings. These results demonstrate the first completely renewable intumescent LbL assembly, which conformally coats every fiber in cotton fabric and provides an effective alternative to current flame retardant treatments.

High Throughput Methods for Polymer Nanocomposites Research: Extrusion, NMR Characterization and Flammability Property Screening

The organic treatment on a layered silicate used in nanocomposite synthesis is the interface between the hydrophilic layered silicate (clay) and hydrophobic polymer in the case of polypropylene. However, the typical synthesis of an organoclay can result in excess organic treatment which can hinder mechanical and flammability benefits. This excess organic treatment may result in plasticization of the polymer matrix, possibly removing some of the mechanical and flammability property benefits provided by the nanocomposite. In this paper, the effects of using Soxhlet Extraction on the Organoclays after synthesis was investigated. Soxhlet extraction times on organoclays were found to have an effect on the mechanical and flammability properties of the resulting polypropylene nanocomposite. The removal of excess organic treatment by Soxhlet extraction resulted in improvements in flex modulus, improved clay dispersion, delayed time to ignition, and lowered heat release rate during burning.

Flame Retardant Polyamide 11 and 12 Nanocomposites: Thermal and Flammability Properties

A large number of parameters influence polymer-nanocomposite performance and developing a detailed understanding of these materials involves investigation of a large volume of the associated multi-dimensional property space. This multi-dimensional parameter space for polymer-nanocomposites consists of the obvious list of different material types under consideration, such as “polymer” and “nano-additive,” but also includes interphase surface chemistry, and processing conditions. This article presents combinatorial library design and high-throughput screening methods for polymer nanocomposites intended as flame-resistant materials. Here, we present the results of using a twin-screwn extruder to create composition-gradient library strips of polymer nanocomposites that are screened with a solid-state NMR method to rapidly evaluate the optimal processing conditions for achieving nanocomposite dispersion. In addition, we present a comparison of a new rapid Cone calorimetry method to conventional Cone calorimetry and to the gradient heat-flux flame spread method.

Synthesis and flame retardant testing of new boronated and phosphonated aromatic compounds

Polyamide (nylon) 11 (PA11) and 12 (PA12) were melt-blended, dispersing low concentrations of nanoparticles, namely nanoclays (NCs), carbon nanofibers (CNFs), and nanosilicas (NSs) via twin-screw extrusion. To enhance their thermal and flame-retardant (FR) properties, an intumescent FR additive was added to the mechanically superior NC and CNF PA11 formulations. For neat and nanoparticle-reinforced PA11 and PA12, as well as for PA11 reinforced by both intumescent FR and select nanoparticles (NC or CNF), decomposition and heat deflection temperatures were measured, as were the peak heat release rates while burning the composites. All PA11 polymer systems infused with both nanoparticles and FR additive had higher decomposition temperatures than those infused with solely FR additive. For the PA11/FR/NC polymer blends, only the 20 wt% FR and 7.5 wt% clay formulation passed the UL 94 V-0 requirement, while all PA11/FR/ CNF formulations passed UL 94 V-0 requirement.

Fire Retardancy of Polymeric Materials, Second Edition

The present report describes the preparation and use of some dimethyl terephthalate derivatives in transition metal-catalyzed coupling reactions to produce new reactive flame retardants. Dimethyl iodoterephthalate and dimethyl 2,5-diiodoterephthalate were successfully employed in the preparation of phosphonic and boronic esters and acids. The latter were tested for heat release with a microcombustion calorimeter (ASTM D7309) to determine the potential for heat release reduction of these flame retardant molecules. The results showed that the addition of boronic or phosphonic acids greatly lowered the heat release, due to a condensed phase (char formation) mechanism. Adding ester groups to the boronic acids or phosphonic acids could either completely remove all flame retardant effects or make the molecule act more like a vapor phase flame retardant. Finally, the various potential flame retardants were solvent blended with a thermoplastic polyurethane to assess their flammability reduction effects by microcombustion calorimetry. The results of these experiments found that the molecules that reduced heat release the most by themselves showed the greatest reduction in heat release in a polyurethane as well, with the boronic acids yielding the greatest reduction in heat release.

Phosphoryl‐Rich Flame‐Retardant Ions (FRIONs): Towards Safer Lithium‐Ion Batteries

When dealing with challenges such as providing fire protection while considering cost, mechanical and thermal performance and simultaneously addressing increasing regulations that deal with composition of matter and life cycle issues, there are no quick, one-size-fits-all answers. Packed with comprehensive coverage, scientific approach, step-by-step directions, and a distillation of technical knowledge, the first edition of Fire Retardancy of Polymeric Materials broke new ground. It supplied a one-stop resource for the development of new fire safe materials.