Statistical Optimization of Ammonium Sulfamate and Urea-Based Fire …
101
Considering all these as background information, in the present study, an attempt is
made, to find newer eco-friendly fire-retardant formulations for jute fabrics using low
cost indigenous common chemicals such as ammonium sulfamate (AS)/sulfamic acid
(SA) along with urea to develop a fire protective jute fabric for its uses as cover fabric
for a temporary structure, brattice cloth in mines and few furnishing and decorative
purposes. The fire-retardant performance of each formulation is investigated for
different concentration and combination in terms of LOI value, fire-spread time,
afterglow time, char length and changes/loss in fabric tenacity, bending length in the
said preliminary study. Thereafter, based on results obtained in the said preliminary
study, a specific statistical optimization is carried out by using the User-Defined
Quadratic Model (UDQM) technique to predict the optimum results for the maximum
level of LOI, the minimum level of char length and loss in fabric tenacity as three
important resultant variables, against two major independent input variables, that
is the concentration of ammonium sulfamate (AS) and concentration of urea for
obtaining suitable response surface equations. For analysis of reaction mechanisms
with functional groups content/pattern, the study of FTIR spectra is also analyzed
and reported.
2 Materials and Methods
2.1 Fabrics and Chemicals
The fabric used in this work was –6 % H 2 O 2 (50 %) bleached fine hessian quality
plain weave jute fabric with 60 ± 2 ends/dm, 60 ± 2 picks/dm, having fabric areal
density of 220 ± 5 g/m
2 . Warp count was 280 ± 5 tex (average 8 lbs/spyndle jute
count) and weft count was 350 ± 5 tex (average 10 lbs/spyndle jute count). The said
jute fabric had 0.80 ± 0.02 mm thickness and the initial whiteness index was 62 ±
2 (Hunter lab scale).
Laboratory grade ammonium sulfamate and sulfamic acid (From Loba Chemicals,
India), Laboratory grade urea (From Loba Chemicals, India), arkofix NEC Plus liquid
(an acrylic poly-carboxylate reactive binder, from erstwhile Clariant India Pvt. Ltd),
ceralube HD liquid [a polyolefin dispersion as softener from erstwhile Clariant India
Pvt. Ltd), Laboratory grade magnesium chloride as catalyst (From Loba Chemicals,
India), saraflam-CWF, a commercially available THPC (Tetra-kis-Hydroxy-methyl
Phosphonium Chloride)-based fire retardant agent obtained from Sarex Chemicals,
Mumbai, India were used in this work.
101
Considering all these as background information, in the present study, an attempt is
made, to find newer eco-friendly fire-retardant formulations for jute fabrics using low
cost indigenous common chemicals such as ammonium sulfamate (AS)/sulfamic acid
(SA) along with urea to develop a fire protective jute fabric for its uses as cover fabric
for a temporary structure, brattice cloth in mines and few furnishing and decorative
purposes. The fire-retardant performance of each formulation is investigated for
different concentration and combination in terms of LOI value, fire-spread time,
afterglow time, char length and changes/loss in fabric tenacity, bending length in the
said preliminary study. Thereafter, based on results obtained in the said preliminary
study, a specific statistical optimization is carried out by using the User-Defined
Quadratic Model (UDQM) technique to predict the optimum results for the maximum
level of LOI, the minimum level of char length and loss in fabric tenacity as three
important resultant variables, against two major independent input variables, that
is the concentration of ammonium sulfamate (AS) and concentration of urea for
obtaining suitable response surface equations. For analysis of reaction mechanisms
with functional groups content/pattern, the study of FTIR spectra is also analyzed
and reported.
2 Materials and Methods
2.1 Fabrics and Chemicals
The fabric used in this work was –6 % H 2 O 2 (50 %) bleached fine hessian quality
plain weave jute fabric with 60 ± 2 ends/dm, 60 ± 2 picks/dm, having fabric areal
density of 220 ± 5 g/m
2 . Warp count was 280 ± 5 tex (average 8 lbs/spyndle jute
count) and weft count was 350 ± 5 tex (average 10 lbs/spyndle jute count). The said
jute fabric had 0.80 ± 0.02 mm thickness and the initial whiteness index was 62 ±
2 (Hunter lab scale).
Laboratory grade ammonium sulfamate and sulfamic acid (From Loba Chemicals,
India), Laboratory grade urea (From Loba Chemicals, India), arkofix NEC Plus liquid
(an acrylic poly-carboxylate reactive binder, from erstwhile Clariant India Pvt. Ltd),
ceralube HD liquid [a polyolefin dispersion as softener from erstwhile Clariant India
Pvt. Ltd), Laboratory grade magnesium chloride as catalyst (From Loba Chemicals,
India), saraflam-CWF, a commercially available THPC (Tetra-kis-Hydroxy-methyl
Phosphonium Chloride)-based fire retardant agent obtained from Sarex Chemicals,
Mumbai, India were used in this work.