Related Experiment Video
Updated: Dec 14, 2025
07:41
Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
Published on: July 19, 2016
8.0K
Potential Synergism between Novel Metal Complexes and Polymeric Brominated Flame Retardants in Polyamide 6.6
Alistair F Holdsworth1,2, A Richard Horrocks1, Baljinder K Kandola1
1Institute for Materials Research and Innovation, University of Bolton, Deane Road, Bolton, Greater Manchester BL3 6HQ, UK.
Polymers
|July 17, 2020
Summary
Zinc and tin tungstates enhance flame retardancy in polymers, acting as effective alternatives to antimony trioxide. These combinations improve thermal stability and reduce smoke, offering a safer flame retardant solution.
Area of Science:
- Materials Science
- Polymer Chemistry
- Fire Safety Engineering
Background:
- Environmental concerns drive the search for safer flame retardants, replacing traditional brominated compounds and antimony trioxide (ATO).
- Polymeric brominated flame retardants (PolyBFRs) are emerging alternatives, but effective co-additives like ATO alternatives are scarce.
- Zinc stannates (ZnS) are known alternatives, but further exploration of other inorganic compounds is needed.
Purpose of the Study:
- To investigate the flame retardant efficacy of aluminium (AlW), tin (II) (SnW), and zinc (ZnW) tungstates combined with two PolyBFRs: brominated polystyrene (BrPS) and poly(pentabromobenzyl acrylate) (BrPBz).
- To evaluate the impact of these tungstate-PolyBFR combinations on the thermal degradation and flammability of polyamide 6.6 (PA66).
- To assess the potential of tungstates as alternatives to antimony trioxide in flame retardant formulations.
Main Methods:
- Thermogravimetric analysis (TGA) for thermal degradation studies.
- Limiting Oxygen Index (LOI) and UL94 tests for flammability assessment.
- Cone calorimetry for heat release rate measurements.
- TGA-Fourier Transform Infrared Spectroscopy (TGA-FTIR) for analyzing degradation products.
- Char residue analysis.
Main Results:
- Zinc tungstate (ZnW) and tin tungstate (SnW) significantly increased LOI values (>26 vol.%).
- ZnW-BrPS and ZnW-BrPBz formulations achieved UL94 ratings of V-2 or higher and substantial char residues (>15 wt.%).
- BrPS-based formulations, particularly with ZnW and SnW, exhibited approximately 50% lower peak heat release rates compared to BrPBz formulations.
- ZnW demonstrated smoke-suppressing properties comparable to zinc stannate (ZnS).
- Synergistic effects were observed, with ZnW acting as a synergist in both pre- and post-ignition stages, especially with BrPS.
Conclusions:
- Zinc tungstate (ZnW) and tin tungstate (SnW) are effective co-additives for polymeric brominated flame retardants (PolyBFRs) in polyamide 6.6.
- ZnW shows promise as a multifunctional additive, enhancing flame retardancy, thermal stability, and smoke suppression, potentially replacing antimony trioxide.
- The study highlights the importance of condensed-phase mechanisms in tungstate-PolyBFR systems, particularly with ZnW.
Keywords:
bromineflame retardantflammabilitymechanistic determinationpolyamide 6.6polymerssmokesynergismthermal analysistungstateszinc stannateMore Related Videos
19:58Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
10.1K
06:34Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
Published on: September 19, 2020
6.2K
Related Concept Videos
01:13Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
7.2K
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
7.2K
01:27Radical Substitution: Allylic Bromination
6.3K
In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...
6.3K
01:20Anionic Chain-Growth Polymerization: Overview
2.4K
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
2.4K
01:14Polymer Classification: Architecture
3.6K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
3.6K
01:23Properties of Organometallic Compounds
1.5K
Organometallic compounds are compounds that contain a carbon–metal bond. Carbon belongs to an organyl group like alkyl, aryl, allyl, or benzyl groups. The metal can be from Group I or Group II of the periodic table, a transition metal, or a semimetal.
1.5K
01:15Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
10.2K
Chlorination and bromination are important classes of electrophilic aromatic substitutions, where benzene reacts with chlorine or bromine in the presence of a Lewis acid catalyst to give halogenated substitution products. A Lewis acid such as aluminium chloride or ferric chloride catalyzes the chlorination, and ferric bromide catalyzes the bromination reactions. During the bromination of alkenes, bromine polarizes and becomes electrophilic. However, in the bromination of benzene, the bromine...
10.2K