Phosphine Oxide Containing Poly(pyridinium salt)s as Fire Retardant Materials.

Bidyut Biswas,Pradip K Bhowmik,Asanga D Ranasinghe,Maksudul M Alam,Kisholoy Goswami,Alexi K Nedeltchev,Haesook Han

doi:10.3390/polym11071141

Bidyut Biswas, Pradip K Bhowmik + Show 5 more

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https://doi.org/10.3390/polym11071141

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Abstract

Six new rugged, high-temperature tolerant phosphine oxide-containing poly(4,4′-(p-phenylene)-bis(2,6-diphenylpyridinium)) polymers P-1, P-2, P-3, P-4, P-5, and P-6 are synthesized, characterized, and evaluated. Synthesis results in high yield and purity, as confirmed by elemental, proton (1H), and carbon 13 (13C) nuclear magnetic resonance (NMR) spectra analyses. High glass transition temperatures (Tg > 230 °C) and high char yields (>50% at 700 °C) are determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. These new ionic polymers exhibit excellent processability, thin-film forming, high-temperature resistance, fire-resistance and retardation, coating, adhesion, mechanical and tensile strength, and n-type (electron transport) properties. The incorporation of phosphine oxide and bis(phenylpyridinium) moieties in the polymer backbones leads to high glass transition temperatures and excellent fire retardant properties, as determined by microcalorimetry measurements. The use of organic counterions allows these ionic polymers to be easily processable from several common organic solvents. A large variety of these polymers can be synthesized by utilizing structural variants of the bispyrylium salt, phosphine oxide containing diamine, and the counterion in a combinatorial fashion. These results make them very attractive for a number of applications, including as coating and structural component materials for automobiles, aircrafts, power and propulsion systems, firefighter garments, printed circuit boards, cabinets and housings for electronic and electrical components, construction materials, mattresses, carpets, upholstery and furniture, and paper-thin coatings for protecting important paper documents.

Highlights

Polymers are extensively used in our everyday lives due to their tunable properties and ease of processing
We report on the design, synthesis, characterization, and evaluation of properties and the performance of six new phosphine oxide-containing poly(4,40 -(p-phenylene)-bis(2,6diphenylpyridinium)) ionic polymers—P-1, P-2, P-3, P-4, P-5, and P-6 (Figure 1)—using the ring-transmutation polymerization reaction
P-6 over time in seconds as measured by microcalorimetry. It provides useful were observed (Figure 13). These results indicate that the phenyl phosphine oxide-containing ionic polymers

Summary

Introduction

Polymers are extensively used in our everyday lives due to their tunable properties and ease of processing. These qualities render polymers useful for applications ranging from adhesives and lubricants to structural components and windows for aircrafts. Common polymers are highly combustible, and produce toxic gases and smoke during combustion. The development of polymers with fire retardant properties is a major challenge. Regulations have required significant improvement of the fire performance of materials used in construction, transportation, and clothing. Some fire resistant materials containing bromine or chlorine moieties are being phased out due to their detrimental effects on health and the environment during combustion

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