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Cotton fabrics can be dyed with reactive and/or direct dyes in aqueous baths under certain specific conditions of pH, salt, temperature, time, etc., and rendered fire retardant through reaction with reactive phosphonopropionamide compounds. In the presence of reactive tertiary amines and reactive phosphorous derivatives, cotton fabrics can be dyed with reactive, direct or acid dyes in the absence of the usual added alkalis and salts, and in the mean time, the fabric becomes fire retardant with wash and wear properties. To verify such claims, reactive aminating agents are synthesized by reacting different amine compounds that have various numbers of amino groups with acryl amide and formaldehyde. The pad-dry-cure technique is applied to treated fabrics with aqueous finishing formulations that contain dyestuff and reactive amine-compounds; the cotton fabric will simultaneously impart reactive dyeing, easy-care inishing and fire-retardant properties. Systematic studies show that in the presence of 6% weight/weight, reactive amine in an aqueous formulation yields cotton fabric with the least loss in tensile strength and elongation at break, and an enhancement to the crease recovery angle. By adding the dyestuff to the aqueous formulation at fixed nitrogen content for treated cotton (0.2%) under identical dyeing conditions, the colour strength (K/S) increases for dyed cotton. The fastness properties of the dyed fabric are improved or remain unaltered for the three types of dyestuffs used

The growth in the development of flame resistant and intumescent paints has been brought about by successive legislation and by the increasing awareness in recent years of the problem that paints can cause. The importance of developing these paints was highlighted during the Second World War when the Navy found that steel ships were no guarantee against fire loss. This was due to the accumulation of multiple layers of paint material providing material that was sufficiently flammable to spread fire from one sealed compartment to another by heat transmitted through the bulkhead. Fire remains an ever‐present hazard on ships and consequently it becomes commonsense to paint the internal structure and fitments wherever possible with a paint that will tend to resist flames. In this article we examine the various factors involved and the pigments that will enhance this property in any paint specification.

In the present article, the authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. Here, the main thrust is placed on the spalling phenomenon of concrete elements when exposed to elevated temperatures and fires.

In this context, it has been long established that prolonged thermal insult on concrete members will lead to egress of water, both physically bound as well as those present as water of hydration within the concrete matrix, in the form of steam through microchannels and associated pathways of least resistance, often resulting in the flaking of the surface of the structure. The latter process can ultimately lead to the exposure of the ferrous-based reenforcement elements, for instance, to higher temperatures, thus inducing melting. This, in turn, can result in substantial loss of strength and load-bearing capacity of the structural element that is already undergoing disintegration of its base matrix owing to heat/fire. Even though spalling of concrete structures has long been recognized as a serious problem that can often lead to catastrophic failure of infrastructures, such as buildings, bridges and tunnels, the utility of intumescent coating as a mitigation strategy is relatively new and has not been explored to its fullest possible extent. Therefore, in the latter parts of the review, the authors have endeavored to discuss the different types of intumescent coatings, their modes of actions and, in particular, their wider applicability in terms of protecting concrete elements from detrimental effects of severe or explosive spalling.

Given that spalling of concrete components is still a very serious issue that can result in loss of lives and destruction of critical infrastructures, there is an urgent need to formulate better mitigating strategies, through novel means and methods. The use of the intumescent coating in this context appears to be a promising way forward but is one that seems to be little explored so far. Therefore, a more systematic investigation is highly warranted in this area, especially, as the authors envisage a greater activity in the building and commissioning of more infrastructures worldwide incommensurate with augmented economic activities during the post-COVID recovery period.

The authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. The authors have also included the results from some recent tests carried out at the facilities using a newly commissioned state-of-the-art furnace.