scholarly journals Sol–Gel Treatments to Flame Retard PA11/Flax Composites

Fibers ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 86 ◽  
Author(s):  
Samyn ◽  
Vandewalle ◽  
Bellayer ◽  
Duquesne

This work investigates the efficiency of sol–gel treatments to flame retard flax fabric/PA11 composites. Different sol–gel treatments applied to the flax fabrics were prepared using TEOS in combination with phosphorus and/or nitrogen containing co-precursors (DEPTES, APTES) or additives (OP1230, OP1311). When the nitrogen and the phosphorus co-precursors were used, two coating methods were studied: a ‘one-pot’ route and a successive layer deposition method. For the “one-pot” method, the three precursors (TEOS, DEPTES, and APTES) were mixed together in the same solutions whereas for the different layers deposition method, the three different treatments were deposited on the fibers successively, first the TEOS, then a mix of TEOS/DEPTES, and finally a mix of TEOS/APTES. After deposition, the sol–gel coatings were characterized using scanning electron microscope, electron probe microanalyzer, and 29Si and 31P solid-state NMR. When only TEOS or a mix of TEOS and DEPTES is used, homogeneous coatings are obtained presenting well-condensed Si units (mainly Q units). When APTES is added, the coatings are less homogenous and agglomerates are present. A lower condensation rate of the Si network is also noticed by solid-state NMR. When additives are used in combination with TEOS, the TEOS forms a homogenous and continuous film at the surface of the fibers, but the flame retardants are not well distributed and form aggregates. The flame retardant (FR) efficiency of the different treatments on flax fabrics was evaluated using horizontal flame spread test. The following ranking of the different systems is obtained: TEOS + Additives > TEOS > TEOS + DEPTES ~ TEOS + DEPTES + APTES > multilayers. All the sol–gel coatings improve the flame retardant properties of the flax fabric, except the multilayer treatment. Based on these results, the three most efficient sol–gels were selected to prepare sol–gel-modified flax/PA11 composites. The composite modified with only TEOS showed the best FR properties. Surprisingly, the composite modified with the phosphorus-based flame retardant (AlPi) did not exhibit improved FR properties. This effect was attributed to the fact that the amount of the FR additive deposited on the fabrics was too low.

2011 ◽  
Vol 236-238 ◽  
pp. 1152-1155
Author(s):  
Lei Gao ◽  
Bo Wen Cheng ◽  
Jun Song ◽  
Zeng Geng Guo ◽  
Fei Lu ◽  
...  

This paper has studied the structure and flame-retardant properties of flame-retardant cellulose fiber with DDPSN as flame retardant. The flame retardants was uniformly dispersed in the cellulose /[Amim]Cl Solution to obtain the good spinnable dope, then the dope was wet-spun. Effects of the flame-retardant contention the fiber structure and properties were investigated. The surface of the flame-retardant cellulose fiber was observed using field emission scanning electron microscope (FESEM). Besides, through the Simultaneous thermal analysis, it has been shown that, with the increase of fame retardant, the degree of fame resistance was obviously improved. The flame retardant acted greatly in condensed phase during the fiber degradation and remained mainly in residues after degradation, the experiments show that the flame-retardant properties of flame-retardant cellulose fiber with 20wt% DDPSN was obvious.


1983 ◽  
Vol 1 (2) ◽  
pp. 145-154 ◽  
Author(s):  
John V. Beninate ◽  
Brenda J. Trask ◽  
Timothy A. Calamari ◽  
George L. Drake

Durable phosphorus-based flame retardants were applied to twill fabrics con taining cotton and wool to study the effect of wool on the flame retardancy and physical properties of the blend fabrics. The presence of wool in untreated blend fabrics caused burning rates to decrease and oxygen index values to increase as wool content increased in the blends. These effects were also observed in cotton/ wool blends treated with low levels of the Thps-urea-TMM flame retardant, but were less pronounced in fabrics treated at high levels. Thermogravimetric analyses were conducted to study the thermal degradation of the treated and untreated fabrics. The presence of wool in treated blend fabrics did not sig nificantly change strength retention, area shrinkage and wrinkle recovery values in comparison to similarly treated 100% cotton fabrics.


2006 ◽  
Vol 984 ◽  
Author(s):  
Paul Guerry ◽  
Donna L Carroll ◽  
Phillips N Gunawidjaja ◽  
Prodipta Bhattacharya ◽  
Daniela Carta ◽  
...  

AbstractTo understand amorphous and structurally disordered materials requires the application of a wide-range of advanced physical probe techniques and herein a combined methodology is outlined. The relatively short-range structural sensitivity of solid state NMR means that it is a core probe technique for characterizing such materials. The aspects of the solid state NMR contribution are emphasized here with examples given from a number of systems, with especial emphasis on the information available from 17O NMR in oxygen-containing materials. 17O NMR data for crystallization of pure sol-gel prepared oxides is compared, with new data presented from In2O3 and Sc2O3. Sol-gel formed oxide mixtures containing silica have been widely studied, but again the role and effect of the other added oxide varies widely. In a ternary ZrO2-TiO2-SiO2 silicate sol-gel the level of Q4 formation is dependent not only on the composition, as expected, but also the nature of the second added oxide. Sol-gel formed phosphates have been much less widely studied than silicates and some 31P NMR data from xerogel, sonogel and melt-quench glasses of the same composition are compared. The effect of small amounts of added antibacterial copper on phosphate glass networks is also explored.


2021 ◽  
Vol 891 ◽  
pp. 37-42
Author(s):  
Sheila Shahidi ◽  
Hakimeh Mohammadbagherloo ◽  
Seyedmohammad Elahi ◽  
Sanaz Dalalsharifi ◽  
Rattanaphol Mongkholrattanasit

In this paper, the sol-gel method was used for in-situ synthesis of SiO2 nanoparticles (NPs) on cotton fabrics with tetraethyl orthosilicate (TEOS) in the presence of acid and alkaline indicators. The samples were characterized using by (X-ray diffraction) XRD, (scanning electron Microscopy) SEM, (Inductively coupled plasma) ICP, water drop test and also the flame retardant properties were studied by char yield. The SEM images showed that the nanoparticles are spherical in shape and the acidity or alkalinity of the medium has an effect on the formation of particles. The XRD patterns showed the typical diffraction of amorphous SiO2 (Si-O short-order structure), also ICP analysis showed that by washing the fabrics, the nanoparticles are still present on the fabric, and this indicated the stability of the washing of the fabrics impregnated with the nanoparticles. By in-situ synthesis of SiO2 nanoparticles, the flame retardant properties have been improved significantly and the amount of residual char was increased and samples were observed to be hydrophilic.


2015 ◽  
Vol 30 (6) ◽  
pp. 816-826 ◽  
Author(s):  
Yiren Huang ◽  
Jianwei Yang ◽  
Zhengzhou Wang

Flame-retardant properties of ammonium polyphosphate (APP) and its two microcapsules, APP with a shell of melamine–formaldehyde (MF) resin (MFAPP) and APP with a shell of epoxy resin (EPAPP), were studied in styrene–butadiene–styrene (SBS). The results indicate that APP after the microencapsulation leads to an increase in limiting oxygen index in SBS compared with APP. When dipentaerythritol is incorporated into the SBS composites containing the APP microcapsules, a further improvement in flame retardancy of the composites is observed. The microencapsulation does not result in much improvement of mechanical properties. Moreover, the effect of a compatibilizer (SBS grafted with maleic anhydride) on flame-retardant and mechanical properties of SBS/APP composites was investigated.


2019 ◽  
Vol 2019 ◽  
pp. 1-25 ◽  
Author(s):  
Shaolin Lu ◽  
Wei Hong ◽  
Xudong Chen

Polymer materials are ubiquitous in daily life. While polymers are often convenient and helpful, their properties often obscure the fire hazards they may pose. Therefore, it is of great significance in terms of safety to study the flame retardant properties of polymers while still maintaining their optimal performance. Current literature shows that although traditional flame retardants can satisfy the requirements of polymer flame retardancy, due to increases in product requirements in industry, including requirements for durability, mechanical properties, and environmental friendliness, it is imperative to develop a new generation of flame retardants. In recent years, the preparation of modified two-dimensional nanomaterials as flame retardants has attracted wide attention in the field. Due to their unique layered structures, two-dimensional nanomaterials can generally improve the mechanical properties of polymers via uniform dispersion, and they can form effective physical barriers in a matrix to improve the thermal stability of polymers. For polymer applications in specialized fields, different two-dimensional nanomaterials have potential conductivity, high thermal conductivity, catalytic activity, and antiultraviolet abilities, which can meet the flame retardant requirements of polymers and allow their use in specific applications. In this review, the current research status of two-dimensional nanomaterials as flame retardants is discussed, as well as a mechanism of how they can be applied for reducing the flammability of polymers.


1999 ◽  
Vol 9 (10) ◽  
pp. 2637-2646 ◽  
Author(s):  
Juliette Quartararo ◽  
Michel Guelton ◽  
Monique Rigole ◽  
Jean‐Paul Amoureux ◽  
Christian Fernandez ◽  
...  

2016 ◽  
Vol 698 ◽  
pp. 60-65 ◽  
Author(s):  
Tôru Kyômen ◽  
Miyu Seki ◽  
Minoru Hanaya ◽  
Hiroshi Takashima

Powder samples of (Ca,Sr)TiO3:Er were prepared by a solid-state reaction method. Photoluminescence due to f-f transitions of Er3+ was not induced by band-gap excitation of (Ca,Sr)TiO3 but by f-f transitions of Er3+. An electroluminescent device in which thin films of Ca0.6Sr0.4TiO3:Er and SnO2:Sb are stacked alternately was prepared by sol-gel and spin-coating methods. Very weak electroluminescence due to f-f transition of Er3+ was observed in the device.


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