of 10
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.

DEVELOPMENT OF ECO-FRIENDLY FLAME RETARDANT FABRIC USING PHOSPHOROUS BASED INTUMESCENCES CHEMISTRY | Differential Scanning Calorimetry | Polyester

Category:

Documents

Publish on:

Views: 15 | Pages: 10

Extension: PDF | Download: 0

Share
Description
A novel flame retardant application technique was developed for cotton apparel fabric using spirocyclic pentaerythritol di (phosphoryl chloride) (SPDPC), which was further synthesized into bis diglycol spirocyclic pentaerythritol bisphosphorate (BSPB). The flame retardant agent was then attached to the fabric using a sol-gel process. The treated fabric was tested on a vertical flame tester which showed very high flame retardancy as compared to the untreated cotton. TGA analysis exhibited a slow rate of weight loss and higher ultimate degradation temperature for the FR treated sample. The FR treated sample showed modest loss in strength while retaining 86.4% of its original strength. The fabric’s appearance did not alter and the change in stiffness was insignificant as a result of the FR finish.
Transcript
  International Journal of Advances in Chemistry (IJAC) Vol.3, No. 1/2/3 , August 2015 1   D EVELOPMENT  O F  E CO-FRIENDLY F LAME  R  ETARDANT  F  ABRIC  U SING  P HOSPHOROUS  B  ASED I NTUMESCENCES C HEMISTRY    Subhas Ghosh 1  and Vikas Joshi 2   1,2 Textile Science Laboratory, College of Technology, Eastern Michigan University, Ypsilanti, 48197, Michigan, USA  Abstract:  A novel flame retardant application technique was developed for cotton apparel fabric using spirocyclic  pentaerythritol di (phosphoryl chloride) (SPDPC), which was further synthesized into bis diglycol spirocyclic  pentaerythritol bisphosphorate (BSPB). The flame retardant agent was then attached to the fabric using a sol-gel process. The treated fabric was tested on a vertical flame tester which showed very high flame retardancy as compared to the untreated cotton. TGA analysis exhibited a slow rate of weight loss and higher ultimate degradation temperature for the FR treated sample. The FR treated sample showed modest loss in strength while retaining 86.4% of its srcinal strength. The fabric’s appearance did not alter and the change in stiffness was insignificant as a result of the FR finish.  Keywords :  flame retardant, synthesis, SPDPC, TGA   1.Introduction  Fire retardancy (FR) is an important requirement for apparel and other furnishing textiles. Textile substrate has a high surface area and close contact with skin that created more complications in developing new chemistry. Most effective flame retardant additive and finishes developed during the period between the 1950s and the 1980s raised concerns over the toxicological and environmental consequences of using such chemicals 1 . Recent research studies focused on the development of an alternative to these traditional fire retardant agents. These studies have been conducted mostly on intumescent fire retardants. Horrocks et al. 1  synthesized spirocyclic pentaerythritol di (phosphonyl chloride) (SPDPC) as a char former. SPDPC was applied to the Proban ®  treated cotton fabric, which created further higher level of char formation owing to the presence of Proban ®  and enhanced flame retardancy 5 . It is important to recognize that these intumescent finishes must be substantively attached to the textile fabric without losing required textile properties to achieve wash durability. Char formation on wool keratin and nylon was also studied using polyol phosphoryl chlorides 6 . Nylon 6 and 6, 6 were phosphorylated by SPDPC, cyclic 1, 3-propanediol phosphoryl chloride (CPPC) and cyclic 2, 2-diethyl-1, 3-propanediol phosphoryl chloride (CDPPC). Based on their calculations, the authors suggested that only primary amine groups at the end of the molecular chain are possible phosphorylation sites. When a wool sample was treated with SPDPC, it also improved char formation. The authors found that like Proban-treated cotton, polyamide containing active hydrogen atoms in primary amine groups at the end of the molecular chains can also be phosphorylated by the polyol phosphoryl chlorides SPDPC, CPPC, and CDPPC. Ma et al. 2  synthesized phosphate-polyester co-polymer using SPDPC. The structural properties of polyester were altered as a result of introducing a new monomer into the polyester structure. The fiber’s limiting oxygen index (LOI), glass-transition [t g ], and solubility parameters [ δ ] increased with increasing SPDPC content in the copolymer. Alongi and Ciobanu 3  coated cotton fabric with silica using a sol-gel process. The authors claimed higher fabric flame retardancy and thermal  International Journal of Advances in Chemistry (IJAC) Vol.3, No. 1/2/3 , August 2015 2   stability; however, the probability of an increase in fabric thickness and stiffness were not discussed. Chen et al. 4  reported a flame retardant and anti-dripping finish for poly (ethylene terephthalate) fabric. PET fabric was treated with poly92-hydroxy propylene spirocyclic pentaerythritol bisphosphonate (PPPBP). The authors found reduced flammability and dripping tendency of PET fabrics using a vertical burning test. Gui-Hong Chen et al. 7  investigated flame retardancy of epoxy resins after treatment with bisdiglycol spirocyclic pentaerythritol bisphosphorate (BDSPBP). They found that flame retardancy of the cured epoxy resins significantly increased when BDSPBP loading was 18% w/w. Intumescent flame retardant can be used on apparel only if the applied finish does not alter textile properties suchas strength, stiffness, and appearance. In our investigation, we synthesized SPDPC and converted it into bis diglycol spirocyclic pentaerythritol bisphosphorate (BSPB). This flame retardant solution was attached to the cotton fabric using a sol-gel system that did not alter significantly any textile properties of the fabric. 2. Experimental 2.1 Synthesis of Spirocyclic pentaerythritol diphosphoryl chloride (SPDPC) SPDPC was synthesized using a modified version of the SPDPC synthesis procedure reported by Horrocks 2 . Pentaerythritol, 98% pure, MP 253-258 ºC and phosphorous oxychloride, 99% pure (BP. 105 ºC), and ethylene glycol were obtained from Sigma Aldrich, Inc., and were used as received. Figure 1.SPDPC synthesis and HCl neutralization setup. Pentaerythritol and phosphorous oxychloride were reacted in a three-neck glass reactor at a molar ratio of 0.5:3.5. The reactor was connected to a magnetic stirrer, nitrogen supply, and a cold water condenser with gradual drop-by-drop addition of phosphoryl chloride to pentaerythritol. HCl formed during the reaction was removed into a beaker containing NaOH and phenolphthalein indicator as safety precaution. The temperature was slowly increased to 80 ºC, and reaction was continued for 2 hours. The temperature was further raised to 115 ºC and held for 20 hours. The final milky white product was washed thoroughly with tetrahydrofuran and air dried (80% yield). Scheme 1 shows the reaction schematics for synthesis of SPDPC.  International Journal of Advances in Chemistry (IJAC) Vol.3, No. 1/2/3 , August 2015 3   Figure 2. Reaction schematic of the formation of Spirocyclic pentaerythritol diphosphoryl chloride (SPDPC) 2.2 Synthesis of Bis diglycol Spirocyclic pentaerythritol bisphosphorate (BSPB) Ethylene glycol, 99.8 % pure (B.P 195-198 ºC), was obtained from Sigma Aldrich and was used as received. BSPB was synthesized as reported by reacting purified SPDPC with ethylene glycol at a molar ratio of 0.1:0.25, as shown in the Figure 3 4 .The reaction mixture in the three-neckreactor was heated gradually to 80 ºC and held there for 6 hours. Further temperature was raised to 130 ºC, and the reaction mixture was held there for 4 hours. The end product was washed with diethyl ether to obtain white powder. Figure3.Reaction schematic of the formation of Bis-diglycol Spirocyclic Pentaerythritol Bisphosphorate (BSPB)  International Journal of Advances in Chemistry (IJAC) Vol.3, No. 1/2/3 , August 2015 4   2.3 Synthesis of Bis-silane and Flame retardant (FR) sol The synthesis of silane and sol-gel system, and its attachment to textile substrates, is the unique contribution of this research. Silquest A-Link 25 –Isocyanatopropyltriethoxysilane (B.P. 238) was obtained from Momentive and used as received. Dibutyltindilaurate reagent, acetone (99.9% pure), and ethanol were obtained from Sigma Aldrich and used as received. Bis-silane was synthesized in two steps by reacting BSPB with triethoxysilane in the molar ratio 1:2 in presence of dibutyltindilaurate as catalyst, figure 4. The reaction mixture is heated to 60 ºC and held there for 4 hours in a three-neck glass reactor equipped with nitrogen gas, magnetic stirrer, thermometer, and a circumference condenser. Formation of bis-silane was tested using Fourier transformation infrared spectroscopy (FTIR). The synthesized bis-silane was reacted with ethanol and water to produce a sol system. The pH of the reaction mixture was adjusted between 3.5 and 4 and stirred at 450 rpm, using magnetic stirrer for 15 minutes to produce a sol. Figure 4. Reaction Schematic of formation of Bis-Silane 2.4 Application of the FR component on textile substrate. The synthesized flame retardant sol was applied on a 100% cotton fabric sample (EPI/PPI: 59/47, 3.2 oz/sqyd). The hydroxyl group of the sol-gel flame retardant finish reacts chemically with the cellulose in cotton to form strong covalent bonds, thus attaching the flame retardant finish to cotton substrate 3 .The sol-gel was applied on the cotton substrate using the pad-dry-cure method.
Similar documents
View more...
Tags
Search Related
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks