Austrian Journal of Technical and


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Scopus, Web of ScienceAustriya-11-12,2019 (2) - копия

 
Reference. 
1.Babakulova 
N.B., 
Uysupov 
U.T. 
Some problems of increasing the fire 
resistance and heat resistance of concrete. 
Readings of A.I. Bulatov: Materials of III-
International 
scientific 
and 
practical 
conference (on March 31, 2019) in 5 vol.4: 
Chemical 
technology 
and 
ecology 
in the oil and gas industry. Conference bulletin 
Krasnodar (Russia),2019. 


29 
Kasimov Erkin Umaralievich-professor of a
Tashkent institute Architecture and civyl ingeeniring, 
Abdukadirov Firdavs Bakhtiyorovich-magistr
of a Tashkent institute Architecture and civyl ingeeniring
(Uzbekistan). E-mail:bjd1962@mail.ru 

Fire retardant nanocoating for wood protection 
 
Abstract: In article the disadvantages of intumescent coatings include their instability when 
exposed to external factors, which leads to a short exploitation period—up to 10 years. In addition, 
intumescent type coatings often contain halogen flame retardant agents, which form toxic 
thermolysis products during fire. 
Key words: fire, fire-retardants, flammability, smoke and toxic gases, fillers, 
rheological additives. 
The ideal fire retardant coatings for wood 
should show minimal spread of flame, little to 
no release of smoke and toxic gases, be easily 
applied, demonstrate good wear resistance, 
adhere to substrates, and provide low cost of 
production and application. It is this set of 
properties that should be given to the known 
IFR systems by nanosized additives. 
As follows from recent studies, this can be 
achieved by the use of nanostructured flame 
retardants 
boron 
nanocompounds 
nanooxides, 
nanoclays, 
and others, 
in 
intumescent type coatings. 
Since 
phosphorous 
fire 
retardants correspond to a wide range 
of chemical structures and not only inorganic 
phosphates incorporated as additives in 
polymers, combinations of nanoclays and 
organic 
phosphates, 
phosphinates, 
phosphonates, and red phosphorus were 
reported [1]. Some of these compounds are 
present as chemical groups in grafted polymers 
or copolymers, which can also act for some of 
them as reactive fire retardants. 
Various research work, mainly carried out 
in Asia, mentioning the combination of oMMT 
and red phosphorus [2], have studied ternary 
combinations of oMMT with magnesium 
hydroxide (MH) and red phosphorus in PA6. It 
is well known that MH acts mainly as a fire 
retardant by its endothermal decomposition 
and water vapor release, which occurs over the 
decomposition range of the polymer. A partial 
substitution of 2 wt% MH by oMMT (mixed 
intercalated and exfoliated) in the ternary 
blend allowed significant improvement of fire
performance, observed using cone calorimeter 
and LOI test, to be achieved. The water vapor 
released makes the cross-linking and charring 
of PA6 easier. Moreover, red phosphorus can 
form polyphosphoric acid derivatives, which 
can react with the decomposition products of 
the other components and lead to a stable 
glassy and charred protective layer. 
The combinations of oMMT with aromatic 
phosphates such as triphenyl phosphate (TPP) 
and resorcinol bis(diphenylphosphate) (RDP) 
were investigated by [3] in PS and unsaturated 
vinyl ester resins. Aromatic phosphates did not 
influence the nanostructure created by 
the nanoclays. Synergistic effects on the ability 
to autoextinguish (UL 94 V0) were achieved in 
PS for phosphate loadings of 30 wt%. For 
vinylester resins, synergistic effects were 
found for HRR values with a superior effect on 
char 
formation. 
Table 

shows 
the 
improvement of fire reaction achieved using 
the combination of oMMT and RDP: the peak 
of HRR is decreased and occurs over a longer 
time; nevertheless, total heat release (THR) 
does not change in comparison with RDP 
alone. Strategies based on reactive fire 
retardants associated with clays were proposed 
by various authors. Organophosphorus epoxy 
resins were synthesized by [3] through the 
reaction 
of 
9,10-dihydro-9-oxa-10-
phosphaphenanthrene-10-oxide 
with 
diethylene 
glycol 
ethyl 
ether 
acrylate 
(DGEBA) resin. Addition of 5–7.5 wt% of a 
MMT was added to investigate possible 
synergies. Cone calorimeter tests showed that 
the presence of 3 wt% phosphorus or 7.5 wt% 


30 
clay could improve pHRR values and THR for 
poly(diethylene glycol ethyl ether acrylate) (P-
DGEBA), but no evidence for complementary 
effects for combinations was found (Table 2). 
investigated the flame-retardant effect of 
newly synthesized phosphorus-containing 
reactive amine, which can be used both as a 
cross-linking agent in epoxy resin and as a 
flame retardant. The effect of combining the
organophosphorous amine with oMMT or 
sepiolite was also studied.A combination of 
this amine with 1 wt% oMMT entailed an 
increase in LOI from 21% to 36% in 
comparison with the same percentage of 
oMMT 
and 
reference 
amine 
without 
phosphorus. Similarly, with sepiolite, LOI 
increased from 21% to 34%. Moreover, a V-0 
rating was achieved using organophosphorous 
amine. 
Table 1. Fire Reaction Data for Polyvinyl Ether (PVE) With Organomodified Montmorillonite 
(oMMT) and Resorcinol Bis(Diphenylphosphate) (RDP) at 35 kW/m
2
Irradiance. 

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