scholarly journals Preparation and Characterization of Zinc Hydroxystannate Coated by Aluminum Phosphate and Its Application in Poly(acrylonitrile-co-vinylidene chloride)

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1365 ◽  
Author(s):  
Ji Eun Song ◽  
Ji Su Kim ◽  
Daeyoung Lim ◽  
Wonyoung Jeong

In this study, zinc hydroxystannate ([ZnSn(OH)6], ZHS) was coated with aluminum phosphate (AlPO4, ALP) to prepare the ZHS-ALP composite. During the coating process, the reaction conditions, such as the ALP to ZHS molar ratio, were controlled, and the morphology of the products was characterized by scanning electron microscopy (SEM). The prepared composites were introduced into poly(acrylonitrile-co-vinylidene chloride) (PANVDC), and the change in compatibility between ZHS and the polymer matrix was characterized. The results showed that ALP-ZHS (1:1), which was prepared by ALP-ZHS composite molar ratio of 1:1, could improve the dispersion and compatibility of ZHS in the polymer matrix and decrease the hydrophilicity and viscosity. Moreover, the ALP-ZHS composite had a better flame-retardant effect on PANVDC than ZHS alone. PANVDC could pass the V-0 rating in UL94, particularly the highest limiting oxygen index (LOI) value of 33.2% obtained when the ALP-ZHS (1:1) composite was added to PANVDC.

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2442
Author(s):  
Ji Su Kim ◽  
Ji Eun Song ◽  
Daeyoung Lim ◽  
Heejoon Ahn ◽  
Wonyoung Jeong

To produce flame retardant poly(acrylonitrile-co-vinylidene chloride) (PANVDC) fibers with limiting oxygen index (LOI) values above 28%, flame retardants are added to fibers. Because antimony trioxide (ATO) used widely for PANVDC is suspected as a carcinogen, non-toxic zinc hydroxystannate (ZHS) could be the alternative for reduction of ATO usage. Moreover, a flame retardant efficiency of the combination of ATO with ZHS could be expected because it was reported that ATO resists flame in the gas phase, whereas ZHS reacts in the condensed phase. Therefore, this study discussed the flame retardant mechanisms of ATO and ZHS in PANVDC, and evaluated the efficiency of the combination. PANVDC fibers with ATO and ZHS in 15 phr were produced by wet spinning. When ZHS was added, a more cyclized structure was detected (e.g., 1-methylnaphthalene) through pyrolysis−gas chromatography-mass spectrometry (Py-GC/MS). As a result of SEM-EDX analysis, Sb and Cl hardly remained in char layers of PANVDC-ATO; meanwhile, Zn, Sn, and Cl remained in that of PANVDC-ZHS. This implied that SbCl3 from reaction of ATO and HCl reacts in the gas phase, whereas ZnCl2 and SnCl2 from ZHS and HCl promotes the cyclization reaction of PANVDC in the condensed phase. The LOI values of PANVDC, PANVDC-ATO, and PANVDC-ZHS were 26.4%, 29.0%, and 33.5%, respectively. This suggests that ZHS is a highly effective for PANVDC. Meanwhile, the LOI of PANVDC containing ATO-ZHS mixture is 31.0%. The combination of ATO and ZHS exhibited no efficiency. The addition of ATO and ZHS slightly reduced the tenacities of the fibers, respectively, 3.11 and 3.75 from 4.42 g/den.


2011 ◽  
Vol 320 ◽  
pp. 369-372 ◽  
Author(s):  
Min Yang ◽  
Hong Tao Cui ◽  
Hua Wei Chen ◽  
Qiong Dang

Zinc hydroxystannate was widely used as green flame retardant and smoke suppression agent. In this paper, two different methods were used to prepare the nano-scale zinc hydroxystannate particles. The reaction of tin tetrachloride and zinc oxide was the first way. In the second method, zinc chloride reacted with sodium stannate. The reaction conditions were studied, and the products were characterized by TG/DTA, SEM, and XRD. The best experiment conditions to synthesis zinc hydroxystannate are using sodium stannate and zinc chloride as the raw material, reacting for an half hour at the temperature of 323K, and molar ratio of reactants of 1:1. This will get higher yield, more pure product with regular morphology.


Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 168 ◽  
Author(s):  
Pablo Acuña ◽  
Zhi Li ◽  
Mercedes Santiago-Calvo ◽  
Fernando Villafañe ◽  
Miguel Rodríguez-Perez ◽  
...  

Three types of expandable graphite (EG) differing in particle size and expansion volume, are compared as flame retardant additives to rigid polyurethane foams (RPUFs). In this paper we discuss microstructure, thermal stability, fire behavior, and compression performance. We find that ell size distributions were less homogeneous and cell size was reduced. Furthermore, thermal conductivity increased along with EG loading. Thermogravimetric analysis (TGA) showed that EG only increased residue yield differently. The results indicate that a higher expansion of EG increased the limiting oxygen index (LOI) value, whereas a bigger particle size EG improved the rating of the vertical burning test (UL94). Results from the cone calorimeter test showed that a bigger particle size EG effectively reduced peak of heat release rate (pHRR). Furthermore, a higher expansion, led to a decrease in smoke production (TSP). The combination of both characteristics gives extraordinary results. The physical–mechanical characterization of the EG/RPUF foams revealed that their compression performance decreased slightly, mostly due to the effect of a bigger size EG.


2013 ◽  
Vol 781-784 ◽  
pp. 526-530 ◽  
Author(s):  
Shao Ying Li ◽  
Chun Mei Niu ◽  
Hua Yu Zhong

Series of cationic cassia tora gum (CCTG) were synthesized using 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) as cationic etherifying agent, isopropanol-water solution as dispersing agent, in presence of sodium hydroxide under different reaction conditions. The optimum ratio for preparing the cationic cassia tora gum are that CHPTAC-CTG molar ratio is 0.6:1; NaOH-CHPTAC molar ratio is 1.3:1.The optimum conditions are that reaction temperature is 55°Cand reaction time is 3.5 h. The cold water solubility was improved apparently. The solution transmittance has corresponding relationship with the nitrogen content (N%) in the certain range, and the maximum transmittance is up to 87.2%. N% increased with the increase of reaction time and stable N% can be obtained in shorter reaction time at higher reaction temperature. The products were characterized by 13C-NMR. The heat resistance of CTG and CCTG were analyzed.


2011 ◽  
Vol 399-401 ◽  
pp. 1376-1380
Author(s):  
Li Hua You ◽  
Yin Yin Hui ◽  
Xiang Ning Shi ◽  
Zhi Han Peng

In this study, a novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) poly(melamine 2-carboxyethyl(phenyl) phosphate)(PMCEP) was prepared via the reaction of 2-carboxyethyl (phenyl) phosphinic acid (CEPPA) and melamine (MEL) in two-steps. Meanwhile, the molecular structure of the chemical compound was determined by FTIR,1H-NMR and elemental analysis; and the thermal properties was investigated by means of TGA. Combustion studies revealed high limiting oxygen index (LOI) indicative of better flame-retardancy properties for PBT resin.


Polimery ◽  
2021 ◽  
Vol 66 (6) ◽  
pp. 341-349
Author(s):  
Salah Al-Shukri ◽  
Ayad Tarik Mahmood ◽  
Othman A. Al Hanbali

A new tris-spiro-(3,4-dioxybenzaldehyde)cyclotriphosphazene [PNCHO] was synthesized from the condensation of hexachlorocyclotriphosphazene with 3,4-dihydroxybenzaldehyde in the presence of strong base. Further reaction of the trialdehydic cyclotriphosphazene based molecules [PNCHO] with three different dianilines (benzidine, 4,4'-methylenedianiline and 4,4′-Sulfonyldianiline) resulted in creation of a new poly(tris-spiro-3,4-dioxbenzene)cyclotriphosphazenes with Schiff-base groups [PNSB1-3]. The structures of [PNCHO] and the polycyclotriphosphazenes-schiff base derivatives were characterized by means of FTIR, 1H, 13C NMR and C.H.N elemental analysis. Differential scanning calorimetery (DSC) revealed a relatively high glass transition temperature (135−175°C) of obtained polymers. Thermal gravimetric analysis (TGA) exhibited their good thermal stability (up to 375oC). The char yield was about 36-42% at 700°C. All polymers were self-extinguishable as the LOI (Limiting Oxygen Index) values were above 26% and this meets with the V-0 and V-1, classification (UL-94). No fumes, soot, or toxic gases emission were observed during burning. The polymers obtained can be used as environmentally friendly, flame-retardant materials.


2013 ◽  
Vol 750-752 ◽  
pp. 1164-1167
Author(s):  
Si Chun Shao ◽  
Yi Lun Tan ◽  
Liu Sun ◽  
Li Hua You ◽  
Zhi Han Peng

In this study, a novel flame retardant 1,2-bis (dimelaminium of 1-nitro-3,5-diphospha-4-oxa-3,5-dihydroxy cyclohexane) ethane (EAPM) was synthesized by ethylene diamine tetra (methylene phosphonic) acid (EDTMPA) and melamine in two steps. Meanwhile, its molecular structure was determined by Fourier-transform infrared spectroscopy (FT-IR), elemental analysis, 1H-NMR. The thermal properties were characterized by TG and DTG, which indicated the good thermostability of EAPM for processing and the considerable residual char in the final stage of combustion. The fire performance of composites blended by the novel flame retardant and polypropylene waere investigated by limiting oxygen index (LOI) and vertical burning test. The results demonstrated the treated PP with the optimal flame retardant formulation of 15 w% EAPM, 5 w% charring agent and 10 w% MEL-APP was attached with an LOI of 33.3% and UL-94 V-0 rating.


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