Browse
Submit Data
Databases
API
Help

Dataset Information

21 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Polybenzoxazine Resins with Polyphosphazene Microspheres: Synthesis, Flame Retardancy, Mechanisms, and Applications.

ABSTRACT: Polyphosphazene microspheres were fabricated by ultrasonic-assisted precipitation polymerization using 4,4'-(hexafluoroisopropylidene)diphenol, 4,4'-sulfonyldiphenol, 4,4-(9-fluorenylidene)diphenol, and phenolphthalein to obtain poly[4,4'-(hexafluoroisopropylidene)diphenol]phosphazene (PZAF), poly(4,4'- sulfonyldiphenol)phosphazene (PZS), poly[4,4'-(9-fluorenylidene)diphenol]phosphazene, and poly(phenolphthalein)phosphazene (PZPT) and were incorporated into polybenzoxazines (PBa) to obtain corresponding PZAF/PBa, PZS/PBa, fluorenyl polyphosphazene (PZFP)/PBa, and PZPT/PBa composites. Addition of 5 wt % of PZAF, PZS, PZFP, and PZPT microspheres improved the thermal stability and fire retardancy of PBa resin significantly. Notably, addition of PBa with 5% PZAF led to a 62.5% decrease in the peak heat release rate and 49.3% reduction in total heat release. The role of microspheres in the gas-phase flame-retardancy mechanism in the PBa matrix was studied. Dynamic mechanical analysis results demonstrated that the T g of PBa flame-retardant composites was still around 210 °C compared to 221 °C of pure PBa. Hence, the synthesized PBa composites had potential applications as high flame-retardancy materials.

SUBMITTER: Zhao L

PROVIDER: S-EPMC6893964 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Curing kinetics of phenolphthalein based polyphosphazene towards thermal stability and flame retardancy of polybenzoxazine.

Project description:Phenolphthalein type polyphosphazene (PZPT) microspheres were synthesized by an ultrasound assisted precipitation polymerization method, and their structures were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Benzoxazine/PZPT (Ba/PZPT) hybrid materials were fabricated and cured to prepare polybenzoxazine/PZPT (PBa/PZPT) composites. The effects of PZPT microspheres on the curing kinetics and behaviors of Ba were systematically analyzed and supported by differential scanning calorimetry (DSC) and in situ FTIR. The thermogravimetric (TGA) results demonstrated good thermal stability of the PBa composites incorporating PZPT. The peak of heat release rate and total heat release values of PBa/PZPT-5% composites obviously deceased by 57.8% and 17.3% compared to those of the pristine PBa. Moreover, the smoke released from the PZPT/PBa system significantly reduced with the loading of microspheres. Finally, the dynamical mechanical analysis results demonstrated that the T g of PBa flame retardant composites was approximately 210 °C, not affecting further applications of PBa composites.

| S-EPMC9072657 | biostudies-literature

Modified melamine-formaldehyde resins improve tensile strength along with antifouling and flame retardancy in impregnation of cellulose paper.

Project description:In this study, polyvinyl alcohol (PVA) and benzoguanamine (BG) modified melamine-formaldehyde (MF) resins were used to prepare two high-pressure laminates (HPLs) as well as a pure cellulose paper laminate and core sandwich laminates with the core material of aramid paper (AP) or polypropylene non-woven fabric (PPNF). The tensile strength, flame retardancy and antifouling properties of the modified MF resin laminates were studied and compared with the MF resin laminate. The tensile test results showed that the MF resins modified with BG and PVA improved the tensile strength of the impregnated paper. In comparison with pure kraft cellulose paper laminates, the aramid paper core laminates displayed comparatively higher tensile strength. Antifouling test results indicated that modified MF resin laminates had no obvious change while the MF resin laminate was stained. Thermal stability of the modified resins was investigated by thermogravimetric (TG) analysis and the results showed that the char yield of modified MF resin was higher than that of the unmodified MF resin due to the addition of BG. The modified MF resin laminates exhibited better flame retardancy properties through the analysis of limiting oxygen index (LOI), vertical burning and cone calorimetry (CONE) compared to the MF resin laminate. In addition, the flame retardancy of laminates was further enhanced when prepared with core materials of aramid paper. Scanning electron microscopy analysis of residue char after CONE tests showed that the AP-core laminate formed a dense and stable char layer compared with the loose char layer of the PPNF-core laminate. This study shows a new direction to develop sustainable high-performance flame retardant laminates for commercial decoration application.

| S-EPMC9075157 | biostudies-literature

Melt-Mixed Thermoplastic Nanocomposite Containing Carbon Nanotubes and Titanium Dioxide for Flame Retardancy Applications.

Project description:The study of polymeric nanocomposites is a possible alternative to conventional flame retardants. The aim of the present work is to investigate the effects of carbon-nanotubes (CNT) and TiO2 nanoparticles (NPs) on the thermo-mechanical, flammability, and electrical properties of polypropylene (PP). In this work, PP-TiO2/CNT nanocomposites were obtained with TiO2/CNT mixtures (ratio 1:2) through the melt extrusion process, with different weight percentage of nanoparticles (1, 5, and 10 wt %). The PP-TiO2/CNT nanocomposites were characterized by DSC, TGA, MFI, FTIR, XRD, and SEM. It was possible to determine that the thermal stability of the PP increases when increasing the content of NPs. A contrary situation is observed in the degree of crystallinity and thermo-oxidative degradation, which decreased with respect to pure PP. The TiO2 NPs undergo coalition and increase their size at a lower viscosity of the nanocomposite (1 and 5 wt %). The mechanical properties decreased slightly, however, the Young's modulus presented an improvement of 10% as well as electrical conductivity, this behavior was noted in nanocomposites of 10 wt % of NPs. Flammability properties were measured with a cone calorimeter, and a reduction in the peak heat release rate was observed in nanocomposites with contents of nanoparticles of 5 and 10 wt.

| S-EPMC6680381 | biostudies-literature

Synergistic Effects of Ladder and Cage Structured Phosphorus-Containing POSS with Tetrabutyl Titanate on Flame Retardancy of Vinyl Epoxy Resins.

Project description:The cage and ladder structured phosphorus-containing polyhedral oligomeric silsesquioxanes (DOPO-POSS) have been synthesized through the hydrolytic condensation of 9,10-dihydro-9-oxa-10-phosphenanthrene-10-oxide (DOPO)-vinyl triethoxysilane (VTES). The unique ladder and cage-ladder structured components in DOPO-POSS endowed it with good solubility in vinyl epoxy resin (VE), and it was used with tetrabutyl titanate (TBT) to construct a phosphorus-silicon-titanium synergy system for the flame retardation of VE. Thermal stabilities, mechanical properties, and flame retardancy of the resultant VE composites were investigated by thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA), three-point bending tests, limiting oxygen index (LOI) measurement, and cone calorimetry. The experimental results showed that with the addition of only 4 wt% DOPO-POSS and 0.5 wt% TBT, the limiting oxygen index value (LOI) increased from 19.5 of pure VE to 24.2. With the addition of DOPO-POSS and TBT, the peak heat release rate (PHRR), total heat release (THR), smoke production rate (SPR), and total smoke production (TSP) were decreased significantly compared to VE-0. In addition, the VE composites showed improved thermal stabilities and mechanical properties comparable to that of the VE-0. The investigations on pyrolysis volatiles of cured VE further revealed that DOPO-POSS and TBT exerted flame retardant effects in gas phase. The results of char residue of the VE composites by SEM and XPS showed that TBT and DOPO-POSS can accelerate the char formation during the combustion, forming an interior char layer with the honeycomb cavity structure and dense exterior char layer, making the char strong with the formation of Si-O-Ti and Ti-O-P structures.

| S-EPMC8122454 | biostudies-literature

Flame Retardancy Index for Thermoplastic Composites.

Project description:Flame Retardancy Index, FRI, was defined as a simple yet universal dimensionless criterion born out of cone calorimetry data on thermoplastic composites and then put into practice for quantifying the flame retardancy performance of different polymer composites on a set of reliable data. Four types of thermoplastic composites filled with a wide variety of flame retardant additives were chosen for making comparative evaluations regardless of the type and loading level of the additive as well as the irradiance flux. The main features of cone calorimetry including peak of Heat Release Rate (pHRR), Total Heat Release (THR), and Time-To-Ignition (TTI) served to calculate a dimensionless measure that reflects an improvement in the flame retardancy of nominated thermoplastic composites with respect to the neat thermoplastic, quantitatively. A meaningful trend was observed among well-classified ranges of FRI quantities calculated for the studied dataset on thermoplastic composites by which "Poor", "Good", and "Excellent" flame retardancy performances were explicitly defined and exhibited on logarithmic scales of FRI axis. The proposed index remains adaptable to thermoplastic systems whatever the polymer or additive is.

| S-EPMC6473221 | biostudies-literature

One-Pot Synthesis of Cyclomatrix-Type Polyphosphazene Microspheres and Their High Thermal Stability

Project description:Highly cross-linked

| S-EPMC10018513 | biostudies-literature

Morphology-Controlled Synthesis of Polyphosphazene-Based Micro- and Nano-Materials and Their Application as Flame Retardants.

Project description:Common flame retardants, such as halogen-based materials, are being phased-out owing to their harmful environmental and health effects. We prepared poly-(cyclotriphosphazene-co-4,4'-sulfonyldiphenol) (PZS) microspheres, nanotubes, capsicum-like nanotubes, and branched nanotubes as flame retardants. An increase in reaction temperature changed the morphology from nanotubes to microspheres. A PZS shape had a positive effect on the flame retardancy of polyethylene terephthalate (PET). The PZS with a capsicum-like nanotube morphology had the best flame retardancy, and the PET limiting oxygen index increased from 25.2% to 34.4%. The flame retardancy capability was followed by PZS microspheres (33.1%), branched nanotubes (32.8%), and nanotubes (32.5%). The capsicum-like nanotubes promote the formation of highly dense and continuous carbon layers, and they release a non-combustible gas (CO2). This study confirms polyphosphazene-based flame retardants as viable and environmentally-friendly alternatives to common flame retardants. It also presents a novel and facile design and synthesis of morphology-controlled nanomaterials with enhanced flame retardant properties.

| S-EPMC9144817 | biostudies-literature

Flame Retardancy of Bio-Based Polyurethanes: Opportunities and Challenges.

Project description:Sustainable polymers are emerging fast and have received much more attention in recent years compared to petro-sourced polymers. However, they inherently have low-quality properties, such as poor mechanical properties, and inadequate performance, such as high flammability. In general, two methods have been considered to tackle such drawbacks: (i) reinforcement of sustainable polymers with additives; and (ii) modification of chemical structure by architectural manipulation so as to modify polymers for advanced applications. Development and management of bio-based polyurethanes with flame-retardant properties have been at the core of attention in recent years. Bio-based polyurethanes are currently prepared from renewable, bio-based sources such as vegetable oils. They are used in a wide range of applications including coatings and foams. However, they are highly flammable, and their further development is dependent on their flame retardancy. The aim of the present review is to investigate recent advances in the development of flame-retardant bio-based polyurethanes. Chemical structures of bio-based flame-retardant polyurethanes have been studied and explained from the point of view of flame retardancy. Moreover, various strategies for improving the flame retardancy of bio-based polyurethanes as well as reactive and additive flame-retardant solutions are discussed.

| S-EPMC7361950 | biostudies-literature

Enhanced flame retardancy of polyethylene/magnesium hydroxide with polycarbosilane.

Project description:Polycarbosilane (PCS) was used for surface modification of magnesium hydroxide (MNH) to enhance the flame retardant effectiveness by forming cohesive binding between MgO particles with ceramic adhesive. Chemical interaction and ceramic reaction were revealed between PCS and MNH, which made for a compact, thermal stable and ceramic-like barrier during the combustion of polyethylene (PE). The flame retardancy of PE/MNH/PCS composites was greatly enhanced and a limiting oxygen index (LOI) of 35.0 was achieved at the PCS/MNH ratio of 4/26 in the composite with 30 wt.% PCS modified MNH. Such results were superior in terms of high LOI value at low global content of MNH. Thanks to the better shielding effect of the integrated and self-supporting ceramic char, the peak heat release rate (p-HRR) and the total heat release (THR) of PE/MNH/PCS composites with 50 wt.% PCS modified MNH were remarkably decreased by 36% and 25% in comparison with PE/MNH with 50 wt.% MNH, respectively. The ceramic reaction between PCS and MNH, the superior thermal stability due to crosslinked PCS and the good barrier function of cohesive ceramic layer play important roles in the effective flame retardant mechanism.

| S-EPMC6160472 | biostudies-literature

Synthesis of Layered Double Hydroxides with Phosphate Tailings and Its Effect on Flame Retardancy of Epoxy Resin.

Project description:In this work, phosphate tailings (PTs) were used as raw materials for the preparation of Ca-Mg-Al layered double hydroxides (LDHs-1) and Ca-Mg-Al-Fe layered double hydroxides (LDHs-2) by co-precipitation method. The as-prepared samples were characterized by FT-IR, SEM, XRD, and XPS and applied as a flame retardant to improve the fire safety of epoxy resin (EP). The results showed that both LDHs-1 and LDHs-2 exhibited layered structure and high crystallinity. Compared with neat EP, the value of limiting oxygen index (LOI) increased from 25.8 to 29.3 and 29.9 with 8 wt% content of LDHs-1 and LDHs-2, respectively. The flame retardant properties of the composite material were characterized by cone calorimeter (CC), and the results showed that the peak value of the smoke production rate (SPR) decreased more than 45% and 74%, total smoke production (TSP) reduced nearly 64% and 85% with the addition of LDHs-1 and LDHs-2. Meanwhile, the value of the total heat release (THR) reduced more than 28% and 63%. The conversion from LDHs to layered double oxide (LDO) might be conducive to the fire safety of EP. Moreover, the transformation of Fe-OH to Fe-O could promote the early cross-linking of polymer. In summary, LDHs-2 could significantly improve the carbonization process of EP and suppress the smoke released during the combustion process.

| S-EPMC9268921 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data