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Most coatings have four basic components. These are the resin, solvent, pigment and additive systems [5] but the resin or binder is the key ingredient. Continuing environmental legislation in many countries along with geopolitics such as oil production are ensuring that chemists are increasingly turning to waterborne technology for paint/coatings and since resins or binders are the most ...
While water-based lacquer's fumes are considerably less hazardous, and it does not have the combustibility issues of solvent-based lacquers, the product still dries fairly quickly. Even though its odor is weaker, water-based lacquers can still produce airborne particulates that can get into the lungs, so proper protective wear still needs to be ...
Polyurethane synthesis, wherein the urethane groups −NH−(C=O)−O− link the molecular units A kitchen sponge made of polyurethane foam . Polyurethane (/ ˌ p ɒ l i ˈ jʊər ə ˌ θ eɪ n,-j ʊəˈr ɛ θ eɪ n /; [1] often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links.
Many flame retardants degrade into compounds that are also toxic, and in some cases the degradation products may be the primary toxic agent: Halogenated compounds with aromatic rings can degrade into dioxins and dioxin-like compounds , particularly when heated, such as during production, a fire, recycling, or exposure to sun. [ 22 ]
Polyurethane dispersion, or PUD, is understood to be a polyurethane polymer resin dispersed in water, rather than a solvent, although some cosolvent may be used.Its manufacture involves the synthesis of polyurethanes having carboxylic acid functionality or nonionic hydrophiles like PEG (polyethylene glycol) incorporated into, or pendant from, the polymer backbone. [1]
Spray foam insulation or spray polyurethane foam (SPF) is an alternative to traditional building insulation such as fiberglass. A two-component mixture composed of isocyanate and polyol resin comes together at the tip of a gun, and forms an expanding foam that is sprayed onto roof tiles, concrete slabs, into wall cavities, or through holes ...
Moisture cured polyurethane–urea coatings have been made by reacting 1,2,3-triazole rich polyether polyols with HMDI at NCO/OH eq. ratio of 1.2 to obtain isocyanate-terminated polyurethane prepolymers. The prepolymers were cured under atmospheric moisture to make polyurethane–urea free films.
For example, instead of forming toxic, flammable gasses in abundance, polymers prepared with incorporation of cyclotriphosphazene rings give a high char yield upon combustion. [3] Polysialates ( polymers containing frameworks of aluminum , oxygen , and silicon ) are another type of inorganic polymer that can be thermally stable up to ...