(REFEREED RESEARCH) INVESTIGATION OF BURNING BEHAVIOR OF POLYESTER FABRIC WITH USING NATURAL STRUCTURED FLAME RETARDANT AGENT DOĞAL YAPIDA GÜÇ TUTUŞUR MADDE KULLANIMI İLE POLYESTER KUMAŞIN YANMA DAVRANIŞININ İNCELENMESİ Zeynep ÖMEROĞULLARI*, Dilek KUT Uludağ University, Department of Textile Engineering, Bursa, Turkey Received: 28.01.2011 Accepted: 29.09.2011 ABSTRACT This paper presents the use of natural structured flame retardant (FR) agent in padding treatment to confer a fire-resistant character to polyester fabrics. The flame retardant agent was obtained from limestone and consisted of any industrial additives and chemical materials. The surface of treated polyester fabric was characterized by FT-IR (ATR) and (SEM). The fire retardant character of the treated fabrics was investigated by LOI measurements. The flame retardancy effect and melt dripping behaviors of FR agent were also investigated. Washing resistances of padded fabrics were examined. According to the results, it was observed that there was a 39.5 % increase in the LOI value and treated polyester fabric was burned in a long time and without dripping. Key Words: Flame retardant, LOI, Limestone, Polyester, Padding. ÖZET Bu çalışma, polyester kumaşa güç tutuşurluk özellik kazandırmak için emdirme yöntemi ile doğal yapıda güç tutuşur madde kullanımını sunmaktadır. Güç tutuşur madde kireç taşından elde edilmiş olup, herhangi bir endüstriyel katkı ve kimyasal madde içermemektedir. İşlem görmüş polyester kumaşın yüzey özelliği FT-IR (ATR) ve SEM tarafından karakterize edilmiş olup, güç tutuşurluk özelliği ise LOI ölçümleri ile değerlendirilmiştir. Aynı zamanda, güç tutuşur maddenin erime ve damlama davranışı da araştırılmıştır. Emdirme işlemi yapılmış kumaşların yıkamaya karşı dirençleri incelenmiştir. Sonuçlara göre, LOI değerlerinde % 39.5’luk bir artış görülmüş ve işlem görmüş polyester kumaşın daha uzun sürede damlama yapmadan yandığı gözlenmiştir. Anahtar Kelimeler: Güç tutuşur, LOI, Kireç taşı, Polyester, Emdirme. * Corresponding Author: Zeynep Ömeroğulları, zeynepomeroglu@uludag.edu.tr, Tel:+90 224 2942087 Fax:+90 224 2941903 1. INTRODUCTION or no adverse effect on the textile’s formation of surface barrier layers physical properties; retaining the (2,6). The halogen-containing flame Flame-retardant processes provide textile’s aesthetics and physiological retardants play an important role due textiles with an important performance properties; being produced by a simple to their high efficiency but their toxicity characteristic. While firefighters and process with conventional equipment and corrosion cause environmental emergency personnel require protection and inexpensive chemicals; being problems. Some of them have been from flames as they go about their environmentally friendly and non-toxic restricted to use in Europe. Therefore, duties; floor coverings, upholstery, drapery, (1,3). there is an increasing interest in the commercial carpet, transportation, development of new environmentally military and professional racers’ Although polyester has a good thermal friendly flame retardants to reduce garments, bedding and children’s stability, chemical resistance, and the usage of the common Sb–Br sleepware requirements also need excellent mechanical properties, the formulations (3-6,8). Phosphorus flame-retardant textiles to protect flammability and the poor anti-dripping containing flame retardants for PET themselves from the possible hazards property of PET restrict the range of are generally concerned because of caused by fire (1,2). their applications where specific fire not causing problems of smoke, resistance performance is required The requirements for a commercially toxicity and corrosion. However, (6,7). In general, halogen and halogen– successful flame retardant textile melting dripping is still a big problem antimony systems tend to be flame product have been given as meeting while burning. In fact, it will bring about inhibitors, the phosphorus and boron flammability requirements: having little a second fire (6). Because of halogen-systems tend to enhance charring and 364 TEKSTİL ve KONFEKSİYON 4/2011 containing flame retardants are being was obtained from the conversation of 2.3. Washing process banned for ecological reasons and limestone rocks into water. Limestone new kinds of flame-retardant chemistry is a sedimentary rock composed In order to investigate the effect of which is based on organic phosphonate largely of the minerals calcite and multiple washings, the treated polyester derivatives are much more expensive; aragonite, which are different crystal fabrics were washed five times after their usage should be limited to the forms of calcium carbonate (CaCO ). the finishing process in Arçelik 4120 S 3 absolute minimum (9). The solubility of limestone in water and home type washing machine at short 0 weak acid solutions leads to karst washing program at 40 C for 60 min There are few studies in literature landscapes. Limestone often contains with domestic detergent. reporting about non-dripping flame variable amounts of silica and varying retardant additive aimed at PET. It is amounts of clay, silt and sand carried worthwhile to design an environ- 2.4. LOI test in by rivers. Limestone is partially mentally friendly and effective FRs for soluble, especially in acid (11). To determine the flame retardancy PET which combines non-dripping and characteristics of polyester fabric after fire-proofing property. Therefore, in According to brand registration padding with Firetex, LOI test was padding treatment, we used a natural certificate, it is indicated that Firetex carried out due to the national American flame retardant agent obtained from improves the flame retardant properties standard of ASTM D 2863-77. A limestone which improved the melt of wooden products and also textiles numerical index, the ‘LOI’, is defined dripping behaviors and flame especially in the usage area of curtain as the minimum concentration of retardancy properties of polyester. The fabric, woolen carpet and blanket. In oxygen in oxygen – nitrogen mixture, flame retardancy effect, flammability addition, due to the toxicity tests, it has required to just support downward and melt dripping behaviors were not harmful effects onto environment, burning of a vertically mounted test investigated in this study. human beings and animals. As a result specimen. Hence, higher LOI values of ICP-AES analysis, Ba, Ni and Mg represent better flame retardancy (10). 2. MATERIAL AND METHOD materials were determined in its structure. 2.1. Material 2.5. SEM micrographs Another flame retardant agent (Ruco- In this study, 100 % polyester woven flam PSY) which is commonly used in The surface morphology of untreated curtain fabrics were used as experimental textile industry was supplied by Rudolf and treated polyester fabrics were samples to investigate the flame Duraner Company (Turkey) and used scanned by SEM using ZEISS/ EVO retardancy properties. The fibres of the as a finishing chemical to compare the 40 electron microscope at 10 kV. SEM fabrics were dyed with Dianix S flame retardant properties with Firetex. micrographs of different areas of fabrics disperse dyestuff at 1300C. The The chemical structure of flame were taken under a high vacuum, with properties of polyester fabric used in retardant agent is alkyl-phosphonate BAL-TEC SCD 005 coating device, this study were given in Table 1. and neutral. Specific weight of FR gold-palladium (Au-Pl) coating at 40- agent is 1.27 g/cm3 at 200C. The pH 50 nm thickness. Table 1. Properties of polyester fabric used value of it is 2-5. It has high resistance in this study. to acids and high water. It has no 2.6. FT-IR (ATR) spectroscopy Weave polyester pigments; it provides flame retardancy The properties of FT-IR ATR spectrums of treated and fabric fabric used in the and gives softness to finished fabric study handle. The chemical structure of flame untreated polyester fabrics were investigated by a Thermo Nicolet 6700 Fabric weight retardant agent is alkyl-phosphonate 230 g/m2 and halojen and antimony trioxide free. device in a wave number range Density 80 warp/cm between 525- 4000 cm -1. Fineness 75 denier-36 2.2. Finishing Process filament 2.7. Color Spectrum Warp yarn Twisting 572 Z Tex During the study, it was realized that Color spectrums of treated and untreated Cross the flame retardancy effect of Firetex Flat polyester fabrics were investigated by section on polyester fabrics was decreased a Konica Minolta Spectrophotometer Color Semi-dull when Firetex was diluted with water CM-3600 d. Density 72 weft/cm before padding treatment. For this reason, using 300 ml Firetex without Fineness 150 denier-288 water was found appropriate and treated 3. RESULTS AND DISCUSSION Weft filament with polyester fabrics in padding bath. yarn Twisting 183 Tex Then fabrics were dried at 1500C for 2 3.1. LOI test results Cross Flat/consists of min. LOI % of the untreated and treated section microfibers Color Semi-dull Some of the polyester fabrics were polyester fabrics were shown in Table also padded with 100 g/L Ruco-flam 2. According to LOI test results, it was PSY (pick-up ratio was 70 %), where determined that LOI value was The flame retardant agent (Firetex) the pH of the padding bath was increased from 19.7 to 27.5 and an used in this study was natural between 5-6 pH, the treated fabric was increase of 39.5 % was observed in structured, consisted of any industrial dried at 1300C and cured at 185 0C for the LOI value of polyester fabric which additives and chemical materials, 1-2 min. 100 g/L Ruco-Flam PSY is padded with Firetex. In case of officially registered by Turk Patent the maximum concentration of flame polyester fabric treated with Ruco- Institute (patent number: 2003 36166). retardant agent recommended by the Flam PSY, LOI % was 32.5 after It is colorless, odorless and a clear padding and there was an increase of company. liquid which has pH value of 8.2. Firetex 64.9 %. After washing process, it was TEKSTİL ve KONFEKSİYON 4/2011 365 indicated that LOI % values of all whole fabric (6x14 cm) which treated burned so slowly and symmetrically. padded polyester fabrics decreased. with Firetex was 210 sec, while the Moreover, no dripping and melting of But it should be emphasized that the burning of untreated polyester fabric polyester fabrics treated with Firetex LOI % values of fabrics padded with took approximately 11 sec. So, it was could be seen in the study, despite the Firetex and Ruco-Flam PSY were clearly seen that the burning time of fact that they are the typical characteristics nearly the same after washing fabric treated with Firetex was nearly of polyester. process. 20 times bigger than the time required Table 2. LOI results of untreated and treated for burning of untreated fabric. To As there was no melting or dripping, polyester fabrics. make a right comparison, this burning only carbonization was observed behavior of fabrics treated with Firetex during burning of fabrics treated with Variation of application was also compared with fabrics treated Firetex. But, at the end of pad-dry LOI % of with alkyl-phosphonate-structured FR method, it was realized that the fabric LOI % of Unwashed Five times agent (Ruco- Flam PSY) which is treated with Firetex adsorbed moisture polyester washed commonly used in flame retardant and gave a sense of wetness after fabrics polyester fabrics finishing process. According to results, waiting for half an hour in laboratory Chemicals the time required for burning whole conditions. The photograph of and amounts fabric treated with 100 g/L alkyl- polyester fabric treated with Firetex No FR agent 19.7 19.7 phosphonate-structured FR agent was after burning was shown in Figure 2. 40 sec. 100 g/L was the maximum 100 g/L Ruco- 3.2. SEM micrographs results Flam PSY 32.5 22.1 concentration recommended by the producing company. It was obviously SEM micrographs of untreated, Firetex 300 ml Firetex 27.5 22.8 seen that the burning time of fabric treated polyester fabrics and 100 g/L treated with Firetex was 5 times bigger Ruco- Flam PSY treated polyester On the other hand, burning behavior of than fabric treated with alkyl- fabrics were shown in Figure 2 (a), (b) and (c), respectively. The residues fabrics treated with Firetex was phosphonate-structured FR agent. shown in Figure 2 (b) are denser than investigated and compared with Although LOI % of fabric treated with Figure 2 (a) and (c). This result can be untreated polyester fabric. As a result Firetex was lower than LOI % of fabric attributed to materials like Ba, Ni and of this investigation, it was determined treated with alkyl-phosphonate-structured Mg which present in chemical structure that the time required for burning FR agent (32.5 %), polyester fabrics of Firetex. Figure 1. The photograph of polyester fabric treated with Firetex after burning 366 TEKSTİL ve KONFEKSİYON 4/2011 Figure 2. (a) SEM micrograph of untreated Figure 2. (b) SEM micrograph of Firetex treated Figure 2. (c) SEM micrograph of 100 g/L Ruco- polyester fabric polyester fabric Flam PSY treated polyester fabric Untreated fabric Firetex treated fabric Figure 3. FT-IR (ATR) spectrum of untreated and Firetex treated polyester fabric 3.3. FT-IR (ATR) spectroscopy modes of adsorbed water (12). In the 3.4. Color spectrums results results O–H stretching region, a broad absorption band grows in and this Color spectrums of treated and untreated FT-IR (ATR) spectrum of untreated band has distinct structure. The polyester fabrics were reported below and Firetex treated polyester fabric was distinct feature in this broad band in Table 3. shown in Figure 3. The characteristic appears at 3375.2 cm-1. The bending As seen in Table 3, the color of fabric peaks of the polyester were seen at mode absorption band also determines -1 padded with Firetex was 23.2 % more wave numbers of 1715 cm (aromatic changes in the band structure as a dark when compared with untreated ester C=O tension vibration), 1242 cm-1 function of humidity. fabric. It is considered that the property (aromatic ester C-C-O tension -1 of moisture adsorption of Firetex vibration) and 1096 cm (aromatic While the water pick of untreated fabric ester O-C-C tension vibration). was at 3426.3 cm -1, the water pick of padded fabric which was observed Firetex treated fabric was at 3375.2 during the study (after padding and -1 Characteristic CaCO peaks in the cm because of its continents which drying) caused this high color of 3 spectra do not show any appreciable provide humidity. Since the fabric darkness. Whereas the colors of effects due to the adsorption of water treated with Firetex adsorbed moisture washed fabrics were lighter in on the surface. However, as water after pad-dry process, a sharp peak comparison with untreated fabric, the adsorbs on the surface there is the was obtained at the peak of 3375.2 color of fabric padded with Ruco-Flam -1 appearance and growth of new bands cm which symbolizes hydroxyl groups PSY showed an increase of 7.0 % in associated with the bending (1646 cm-1) that are at the end of the linkages of color darkness. and stretching (3000–3700 cm-1) polyester. TEKSTİL ve KONFEKSİYON 4/2011 367 Table 3. Color spectrums of treated and untreated polyester fabrics CIE LAB ∆E Depth of Color Polyester Fabric L* a* b* (in comparison (in comparison with untreated with untreated Untreated fabric 39.987 -12.931 -12.636 fabric) fabric) Fabric padded with Firetex 29.942 -7.723 -9.576 10.877 23.2 % more dark 5 times washed fabric after padding with Firetex 40.016 -13.876 -13.246 1.524 2.6 % more light Fabric padded with Ruco-Flam PSY 36.253 -11.123 -12.969 3.295 7.0 % more dark 5 times washed fabric after padding with Ruco-Flam PSY 39.474 -12.582 -14.534 1.99 1.2 % more light 4. CONCLUSION treated with Firetex was 5 times bigger and improvement in burning time. than fabric treated with alkyl- However, it was realized that at the As a result of this study, it was phosphonate-structured FR agent. end of the pad-dry process, the fabric determined that Firetex improved the Washing resistances of treated fabrics treated with Firetex adsorbed moisture flame retardancy effect of polyester were also examined. It was indicated and gave a sense of wetness after fabric after treatment. LOI values that LOI % values of all padded waiting for half an hour in laboratory increased from 19.7 to 27.5. There was a polyester fabrics decreased after conditions. 39.5 % increase in the LOI value. washing process. The burning time of fabric treated with The flammability behavior of polyester ACKNOWLEDGEMENT Firetex was 20 times bigger than fabric was also investigated and required time for burning of untreated realized that Firetex treated fabrics This study was supported by The fabric. This burning behavior was also burned so slowly and symmetrically. Commision of Scientific Research compared with fabrics treated with Moreover, there was no dripping or Projects of Uludağ University. The alkyl-phosphonate-structured FR agent melting, only carbonization was watched project number is M (U) 2009/33. which is commonly used in flame during burning. This natural structured retardant finishing process. It was flame retardant agent provided an determined the burning time of fabric increase in flame retardancy properties REFERENCES 1. 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