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31-406: Dopping cement is usually formulated so that it is hard at room temperature, but soft and moldable like putty at 45-65 °C, when it can still be shaped with the fingers. The cement is commercially sold as sticks or flat slabs. With metal dopsticks, a low-melting tin-lead solder can be used for that purpose, instead of a dopping cement. In typical use, a small amount of cement is melted from

62-455: A UPR, the fumarate form is known to react more rapidly with the styrene radical, so isomerization catalysts, such as N,N-dimethylacetoacetamide (DMAA), are often employed in the synthesis process which converts the maleates into fumarates; the isomerization can also be encouraged with increased reaction time and temperature. Within the UPR industry, the classification of the resins is generally based on

93-992: A catalyst present can, therefore, cause charring or even ignition during the curing process. Excessive catalyst may also cause the product to fracture or form a rubbery material. Unsaturated polyesters (UPR) are utilized in many different industrially relevant markets, but in general are used as the matrix material for various types of composites . Glass fiber-reinforced composites comprise the largest segment into which UPRs are used and can be processed via SMC , BMC , pultrusion , cured-in-place pipe (known as relining in Europe), filament winding , vacuum molding , spray-up molding , resin transfer molding (RTM) . Wind turbine blades also use them as well as many more processes. UPRs are also used in non-reinforced applications with common examples being gel coats , shirt buttons, mine-bolts , bowling ball cores , polymer concrete , and engineered stone/cultured marble . In organic chemistry, an ester

124-401: A condensation by-product of esterification reactions, is continuously removed by distillation, driving the reaction to completion via Le Chatelier's principle . Unsaturated polyesters are generally sold to parts manufacturers as a solution of resin in reactive diluent; styrene is the most common diluent and the industry standard. The diluent allows control over the viscosity of the resin, and

155-442: A difunctional (or higher order) acid or acyl halide is reacted with a difunctional (or higher order) alcohol. Polyesters are produced commercially both as saturated and unsaturated resins. The most common and highest volume produced polyester is Polyethylene terephthalate (PET) , which is an example of a saturated polyester and finds utilization in such applications as fibers for clothing and carpet, food and liquid containers (such as

186-502: A glycol-modified PET (PET-G) is used, exceptional properties can be imparted to the resin due to some of the exotic materials used in PET-G production. Tere and PET-UPR resins are used in many applications including cured-in-place pipe. Lichens have been shown to deteriorate polyester resins, as can be seen in archaeological sites in the Roman city of Baelo Claudia Spain. Polyester resin offers

217-433: A special sub-set of Tere resins, known as PET UPR resins, which are produced by catalytically cracking PET resin in the reactor to yield a mixture of terephthalic acid and ethylene glycol. Additional acids and glycols are then added along with maleic anhydride and a new polymer is produced. The end product is functionally the same as a Tere resin, but can often be lower cost to manufacture as scrap PET can be sourced cheaply. If

248-423: A water/soda bottles), as well as films. In unsaturated polyester (UPR) chemistry, unsaturation sites are present along the chain, usually by incorporation of maleic anhydride, but maleic acid and fumaric acid are also used. Maleic acid and fumaric acid are isomers where maleic is the cis-isomer and fumaric is the trans-isomer. The ester forms of these two molecules are maleate and fumarate, respectively. When curing

279-566: Is a basic component of a plumber's toolkit and is often used when replacing plumbing fixtures. Plumber's putty formulations vary but commonly include powdered clay and linseed oil . Other formulas use limestone , talc , or fish oil . RTV silicone or epoxy sealants may be used in place of putty. Plumber's putty contains mineral oils and/or vegetable oils so it can stain porous materials such as marble or some plastics. The oils can also react chemically with some plastics, slowly making them brittle. Certain types of putty also have use in

310-408: Is a material with high plasticity , similar in texture to clay or dough , typically used in domestic construction and repair as a sealant or filler. Although some types of putty (typically those using linseed oil ) slowly polymerise and become stiff, many putties can be reworked indefinitely, in contrast to other types of filler which typically set solid relatively rapidly. Putty, or lime putty ,

341-773: Is a potential carcinogen. Drinking water applications also prefer styrene free. Most polyester resins are viscous, pale coloured liquids consisting of a solution of a polyester in a reactive diluent which is usually styrene, but can also include vinyl toluene and various acrylates . Unsaturated polyesters are condensation polymers formed by the reaction of polyols (also known as polyhydric alcohols ), organic compounds with multiple alcohol or hydroxy functional groups, with unsaturated and in some cases saturated dibasic acids. Typical polyols used are glycols including ethylene glycol , propylene glycol , and diethylene glycol ; typical acids used are phthalic acid , isophthalic acid , terephthalic acid , and maleic anhydride . Water,

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372-595: Is also a participant in the curing reaction. The initially liquid resin is converted to a solid by cross-linking chains. This is done by creating free radicals at unsaturated bonds, which propagate in a chain reaction to other unsaturated bonds in adjacent molecules, linking them in the process. Unsaturation is generally in the form of maleate and fumarate species along the polymer chain. Maleate/fumarate generally does not self-polymerize via radical reactions, but readily reacts with styrene. Maleic anhydride and styrene are known to form alternating copolymers , and are in fact

403-463: Is an epoxy putty used primarily for steel bonding. Milliput is another popular multipurpose epoxy putty. Bondo is a polyester-based automotive body filler, which is commonly used in collision repair. Plumber's putty is the common name encompassing a variety of products of completely different compositions, all used for making watertight seals in plumbing . It is a pliable substance used to make watertight seals around faucets and drains. The putty

434-402: Is decreasing with the prevalence of PVC and metal window frames which use synthetic sealants such as silicone . Glazing putty is traditionally made by mixing a base of whiting (finely ground chalk ) with linseed oil in various proportions. Historically, white lead was sometimes mixed with the whiting. There are a number of synthetic alternatives such as polybutene -based putties, where

465-428: Is formed as the condensation product of a carboxylic acid and an alcohol , with water formed as the condensate by-product. An ester can also be produced with an acyl halide and an alcohol, in which case the condensate by-product is a hydrogen halide . Polyesters are a category of polymers in which ester functionality repeats within the main chain. Polyesters are a classic example of step-growth polymer , in which

496-587: Is made from a mixture of calcium oxide (CaO) and water (H 2 O) in proportions of 38% and 62% by weight respectively, as result, the solution forms hydrated lime (Ca(OH) 2 ) which takes up about a half of the weight. The other putty mixture may be a calcium carbonate (CaCO 3, 750-850 parts) based with an admixture of CaO (ash calcium, 120-180 parts), white cement (40-60 parts), and talc powders in much lower concentrations (fractions). Putty has been used extensively in glazing for fixing and sealing panes of glass into wooden frames (or sashes ), although its use

527-656: The catalyst within the industry, but initiator is a more appropriate term. Transition metal salts are usually added as a catalyst for the chain-growth crosslinking reaction, and in the industry this type of additive is known as a promoter; the promoter is generally understood to lower the bond dissociation energy of the radical initiator. Cobalt salts are the most common type of promoter used. Common radical initiators used are organic peroxides such as benzoyl peroxide or methyl ethyl ketone peroxide . Polyester resins are thermosetting and, as with other resins, cure exothermically. The use of excessive initiator especially with

558-519: The USA also specify them for use as overlays on roads and bridges. In this application they are known AS Polyester Concrete Overlays (PCO). These are usually based on isophthalic acid and cut with styrene at high levels—usually up to 50%. Polyesters are also used in anchor bolt adhesives though epoxy based materials are also used. Many companies have and continue to introduce styrene free systems mainly due to odor issues, but also over concerns that styrene

589-434: The field of terminal ballistics , where the putty can accurately represent the average density of the human body. As such it can be used, for instance, to test the penetrative power of projectiles , or the stopping power of body armour . Modeling clay and play putty, such as Plasticine and Silly Putty are common toys . Polyester resin#Unsaturated polyester Polyester resins are synthetic resins formed by

620-474: The fingers so as to tightly enclose it, except for the part that is to be ground or polished. Alternatively, the stone may be warmed up to that temperature, and a few drops of molten cement can be dropped over it. The dopstick is then placed over the stone, and the cement is pressed around it. The stone can be removed from the dopstick by warming the cement again. Alternatively, the cement can be further cooled with cold water, so that it becomes brittle, and then

651-470: The higher end of UPR products, both because of the relatively higher cost of the isophthalic acid as well as the superior properties they possess. Iso resins are the primary type of resin used in gel coat applications, which is similar to a paint, but is sprayed into a mold before the FRP is molded leaving a coating on the part. Gel coat resins must have lower color (almost clear) so as to not impart additional color to

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682-457: The latter case, hydrates in the putty produce an endothermic reaction to mitigate heat transfer to the unexposed side. In woodworking , water-based putties are more commonly used, as these emit very little odour, are more easily cleaned up and are compatible with water-based and latex sealers. Polyester putty and epoxy putty are thermosetting polymers that can be molded by hand, but become permanently rigid after curing. Pratley Putty

713-522: The maleic acid reacts across one of the double bonds of the DCPD. This product is then used to end-cap the UPR resin which yields a product with unsaturation on the end-groups. This type of resin is referred to as a DCPD resin. Ortho resins comprise the most common type of UPR, and many are known as general purpose resins. FRP composites utilizing ortho resins are found in such application as boat hulls, bath ware, and bowling ball cores. Iso resins are generally on

744-408: The part or so that they can be dyed properly. Gel coats must also have strong resistance to UV-weathering and water blistering. Tere resins are often used when high modulus and strength are desired, but the low color properties of an Iso resin is not necessary. Terephthalic acid is generally lower cost than isophthalic acid, but both give similar strength characteristics to a UPR product. There exists

775-490: The polybutene is a low molecular weight oligomer replacing the linseed oil . Butyl rubber is also added to the mixture to provide some strength and flexibility. Painter's putty is typically a linseed oil -based product used for filling holes, minor cracks, and defacements in wood only. Putties can also be made intumescent , in which case they are used for firestopping as well as for padding of electrical outlet boxes in fire-resistance rated drywall assemblies. In

806-402: The polymer chain via a Diels-alder reaction . This type of resin is known as a Nadic resin and is referred to as a poor man's Ortho, due to sharing many similar properties of an Ortho resin along with the extremely low cost of DCPD raw material. In another process, maleic anhydride is first opened with water or another alcohol to form maleic acid and is then reacted with DCPD where an alcohol from

837-501: The primary saturated acid. For example, a resin containing primarily terephthalic acid is known as a Tere resin, a resin containing primarily phthalic anhydride is known as an Ortho resin, and a resin containing primarily isophthalic acid is known as an Iso resin. Dicyclopentadiene (DCPD) is also a common UPR raw material, and can be incorporated two different ways. In one process, the DCPD is cracked in situ to form cyclopentadiene which can then be reacted with maleate/fumarate groups along

868-654: The reaction of dibasic organic acids and polyhydric alcohols . Maleic anhydride is a commonly used raw material with diacid functionality in unsaturated polyester resins. Unsaturated polyester resins are used in sheet moulding compound , bulk moulding compound and the toner of laser printers . Wall panels fabricated from polyester resins reinforced with fiberglass —so-called fiberglass reinforced plastic (FRP)—are typically used in restaurants, kitchens, restrooms and other areas that require washable low-maintenance walls. They are also used extensively in cured-in-place pipe applications. Departments of Transportation in

899-445: The stone is pried out with a knife. Dopping cement can be made from several materials, including Commercial cements may have other formulations. Formulations with higher melting point, like 65-75 °C, tend to be harder at room temperature and thus hold the stone more firmly. However, they may be too hot to mold with bare fingers; and some gemstones (like opal and turquoise ) are easily damaged by heat. Putty Putty

930-407: The textbook case of this phenomenon. This is one reason that styrene has been so hard to displace in the market as the industry standard reactive diluent for unsaturated polyester resins, despite increasing efforts to displace the material such as California's Proposition 65 . The initial free radicals are induced by adding a compound that easily decomposes into free radicals. This compound is known as

961-399: The tip of a cement stick or from the edge of a cement slab by holding it over an alcohol lamp or similar source of heat. The tip of the dopstick is dipped into the molten cement, which is allowed to cool until it has the consistency of putty. The stone too is separately warmed up to about the same temperature. Then the dopstick is pressed down over the stone, and the cement is pressed with

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