SERISHM : AN ECO-FRIENDLY AND BIODEGRADABLE FLAME RETARDANT FOR FABRICS

Biodegradable and eco-friendly materials are preferred due to less environmental impacts in compare to synthetic and chemical compounds. Serishm is known as a natural protein based material which includes Collagen and has been considered as an ancient coating on textile materials. However, there is a lack of scientific approach and experimental finding to show the capability of using this material as the fire retardant for fabrics. Therefore, the main objective of this work is to investigate the possibility of using Serishm as a natural fire-retardant material. 23 various samples in fabric type (polyester, cotton and cotton/polyester) , Serishm content in 150 cc water (5, 10 and 15 g) were investigated under various conditions of padding pressure (2, 3 and 4 MPa), padding times (2, 3 and 4 times) and method of coating (pad dry cure, conventional method and injection molding of silicone-resin. Moreover, as cotton fabrics were highly flammable, various nano-silica contents (2, 4 and 8%) were used to determine the most appropriate condition for cotton fabrics. Flame retardancy and physical properties of each sample were evaluated. According to the test results, polyester fabric coated by Serishm showed better flame retardancy in compare to cotton and cotton/polyester fabrics. By increasing the padding times, the sample was capable to stop the firing procedure. The conventional coating showed better results in compare to padding methods, while the injection molding was the most appropriate method in compare to the other methods. It was concluded that the protein resin could completely penetrate into the fabric texture during injection molding. Therefore, by applying Serishm through injection method even cotton fabrics showed better flame retardancy.


INTRODUCTION
Nowadays, the main environmental concerns are due to the production and utilization of chemical compounds more than ever before [1][2][3][4][5].Flame-retardants (FR) are considered as a group of anthropogenic environmental contaminants as well as heavy metals [6] which are widely used in many applications [7].Many researchers have focused on the concentrations [8] and effects of chemical compounds such as brominated [9], organo-phosphorus flame retardants [10] and many others on human health, environment and indoor air [11].Additionally, some other researchers have focused on using biodegradable and eco-friendly compounds to be used as the flame retardant materials.
In compare to synthetic and chemical compounds, biodegradable and ecofriendly materials are preferred due to less environmental impacts.Sharma et al [12,13] have compared various eco-friendly methods of flame retardant treatments of cellulose-based materials and indicated that there is still the need of developments in this case.Most of previous rdants but less research studies have focused on hazards of using flame reta works have been done in the case of introducing green flame retardants .Therefore, the main objective of the present work is to investigate the capability of using a green material as a suitable fire retardant for fabrics.Serishm is an ancient animal based material which was mostly used as a binder of fabric/wood in paintings for many years ago [14], and laterally was replaced by the conventional white wood glue.It is mainly made from a protein based material including Collagen.Collagen is basically a biodegradable and natural protein derived from animals and fishes [15].However, there is a lack of scientific experimental results to show the capability of using this material as the natural fire retardant for fabrics.Therefore, in the present work with the aim of introducing a biodegradable and eco-friendly material such as Serishm, the possibility of using this material in flame retardant applications such as textile fabrics was investigated.

MATERIALS AND METHODS
First of all, Fourier Transform Infrared Spectroscopy (FTIR) analysis was carried out on Serishm powder.The Serishm powder was mixed by KBr powder and was pressed carefully to be in appropriate dimension for FTIR test.By changing some factors affecting flame retardancy 23 samples were fabricated in order to investigate the possibility of using Serishm as a natural flame retardant coating for fabrics.The following independent variables were selected which could affect the flame retardancy:

SERISHM: AN ECO-FRIENDLY AND BIODEGRADABLE FLAME RETARDANT FOR FABRICS
The samples characteristics are presented in table 1.

RESULTS AND DISCUSSION
The results of FTIR analysis are presented in figure 7. The results of physical properties and fire retardancy tests are presented in table 2.     According to the results, samples 22 and 23 did not show any significant change after being exposed to flame.Therefore, the flame retardancy extremely depends on the method of treatment.However, by increasing the amount of resin on fabric, the thickness increases while reducing the flexural rigidity and permeability.Although cotton fabric is highly flammable, by applying Serishm through injection molding, a flame retardant fabric is achieved.Totally, it is concluded that coating polyester fabrics by Serishm through injection molding method offers a suitable flame retardant material.Therefore, Serishm as a biodegradable and natural flame retardant which has no serious impacts on environment can be used instead of synthetic resins.

CONCLUSION
Biodegradable and eco-friendly materials are preferred due to less environmental impacts in compare to synthetic and chemical compounds.
Serishm is considered to be a protein based material and a suitable fire retardant for fabrics.However, there is a lack of scientific experimental results to show the capability of using this material as the fire retardant for fabrics.Therefore, in this work, 23 various samples in fabric type, Serishm content and nano-silica content were investigated under various conditions of pad pressure, padding times and method of coating.Flame retardancy and physical properties of each sample were evaluated.According to test results, polyester fabric coated by Serishm showed better flame retardancy in compare to cotton and cotton/polyester fabrics.By increasing the padding times, the sample was capable to stop the firing procedure.The conventional coating method showed better results in compared to padding method.However, by increasing the amount of resin on fabric, the thickness increases while reducing the flexural rigidity and permeability.
The flame retardancy extremely depends on the method of treatment.Although cotton fabric is highly flammable, by applying Serishm through injection molding, a flame retardant fabric is achieved.It was concluded that the protein resin penetrates completely into the fabric texture during injection molding.Hence, by applying Serishm through injection method even cotton fabrics showed better flame retardancy.
Totally, it is concluded that coating polyester fabrics by Serishm through injection molding method offers a suitable flame retardant material.Therefore, Serishm as a biodegradable and natural flame retardant which has no serious impacts on environment can be used instead of synthetic resins.As the flame retardant treatment increased the flexural rigidity and the thickness of fabrics, the authors suggest using softener and investigate other aspects of this work for future.

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Fabric type (polyester, cotton and cotton/polyester) 2-Serishm content in 150 cc water (5, 10 and 15 g) 3-Pad pressure (2, 3 and 4 MPa) 4-Padding times (2, 3 and 4 times) 5-Method of coating (pad dry cure, conventional method and injection molding of silicone-resin) 6-Nano-silica content for cotton fabrics (2, 4 and 8%) The flame spread time, fired area and the self-extinguishing ability were considered as the response variables.Fire retardancy of each sample was investigated through edge and surface ignition tests.The effects of Serishm contents and fabric type were investigated at the pad pressure of 2 MPa, Stenter temperature of 100 o C and curing time of 2 minutes.Baking procedures were carried out on cotton, polyester and cotton/polyester fabrics at the temperatures of 130, 150 and 170 o C up to 5, 3 and 1 minutes, respectively.The effects of Stenter pressure on cotton fabric were investigated at the Serishm contents of 10 grams per 150 cc water, drying temperature of 100 o C and baking temperature of 130 o C up to 5 minutes.The padding procedure was carried out on all types of fabrics for 4 times to investigate the effects of padding times.Contents List available at RAZI Publishing Environment & Ecosystem Science (EES) Journal Homepage: http://www.razipublishing.com/journals/environment-and-ecosystemISSN:2521-0882 (Print) ISSN : 2521-0483 (Online)

1 Figure 1 :Figure 2 :
Figure 1: a) Thickness test device b) Flexural rigidity test device c) Permeability test device

Figures 3
Figures 3 and 4 show the results of edge and surface ignition tests, respectively.

Figure 3 :
Figure 3: comparing the edge ignition time

Figure 4 :
Figure 4: Comparing the surface ignition time

Table 2 :
the physical properties and results of fire retardancy tests for each sample

Table 4 :
Test of Homogeneity of Variances in comparing means of edge

Table 5 :
Test of Homogeneity of Variances in comparing means of