Adhesive flexibility

Uses of EtCell include films, adhesive, flexible lacquers, varnishes-, plastics, electrical insulators, moulding powders, jelled expls such as used in Bangalore Torpedo (See Vol 2, pp B16 ff), inhibitor tape for rockets and proximity fuzes (Refs 8 10)... 

The polyester type polyols used in polyurethane laminating adhesives are produced by the direct esterification of polyfunctional carboxylic acids and glycols. Polyester polyols provide the soft segment in polyurethane products giving the adhesive flexibility. Ester groups of the polyol also contribute to adhesion. Polyester polyols provide limited wetting and adhesion of olefinic surfaces with amide slip additives (in contrast to polyether polyols). Typical examples include adipic acid, caprolactone, maleic acid and isophthalic based polyester polyols. 

The polymers with (meth)acrylic chain ends can be crosslinked with peroxides or by UV irradiation 175 176), a procedure used for adhesives. Flexibility, resistance to attack by hydrolysis, heat, and ozone, as well as improved modulus and strength of the plastic adhesives are the characteristic effects of this modification on properties. 

Film performance Film resistance tests are for hardness, abrasion, adhesion, flexibility, impact, scrubbability, and chemical and water resistance. 

MIL-A-24179A NOTICE 1 (SHIPS) Adhesive, Flexible Unicellular — Plastic Thermal Insulation, 22 June 1987, 1 p Notice + 2 pp amend + 11 pp base spec (FSC 8040) (SH)... 

The UV-curing polyacrylates are particularly variable in terms of flexibility, viscosity adjustment (microdosing in the pg range), flow behavior (thixotropy), and adhesion. Flexibility is particularly important in hard-soft combinations such as plastic-metal and glass-plastic in order to compensate for expansion due to temperature variations. UV-curing adhesives are also used for cladding applications in composites. 

Castor oil is used in many PU applications such as coatings, cast elastomers, thermoplastic elastomers, rigid foams, semi-rigid foams, sealants, adhesives, flexible foams and so on [29,36,41-43,47, 48]. 

Hydrogenated castor oil is a solid with a melting point of 82-86 °C, having similar hydroxyl number to castor oil, of around 160-162 mg KOH/g. Hydrogenated castor oil is used in coatings and gives adhesion, flexibility, water repellency and chemical resistance [36]. 

DPR . [Hardman] Ptdyisoprene used for potting, sealants, caulk, adhesives, flexible rubber molds. 

Lexorez. [Inolex] Polyadipates or polyphthalates polyol to polyurethane formulatitm, adhesives, flexible coatings, castable elastomers. 

An increasingly widespread use of acrylates in the leather field is as a component of water-based finishes. In such cases, the acrylate improves tho adhesion, flexibility, and leveling of the finish, and depending upon the amount and type used, improves the washability. The softer t q)es are often used as plasticizers for aqueous disperrions of other resins which are too brittle, without modification, for flexible coatings. 

The hydrated adhesive is more flexible than strongly crosslinked adhesive. Flexibility is a useful mechanical property for an adhesive to bond to a mobile or elastic substratum (e.g., PDMS, biofilm). The web-Hke structure of the hydrated adhesive is rather more able to adjust to movements of the substratum (molecular mobility of the polymer backbone, compression or extension of elastic material) than the rigid, strongly crosslinked cement. 

The essential ingredients of a free-radical adhesive formulation are an acrylate-terminated prepolymer and a photoinitiator. A wide range of prepolymers can be acrylated, including epoxies, urethanes, polyesters, polyethers, and rubbers. Those most commonly used in adhesive formulations are epoxy and urethane acrylates. Epoxy acrylates have properties similar to those of the parent epoxy resin, with excellent adhesion, chemical resistance, and toughness. Urethane acrylates, on the other hand, are noted for their high reactivity, good adhesion, flexibility, and tear resistance. 

Epoxy resins are generally not used alone but require a reaction partner in order to be cured (hardened). A large number of reaction partners may be used for curing at elevated or at room temperature. The cured films have high adhesion, flexibility, hardness, abrasion resistance, resistance to chemicals, and corrosion protection. In 1995 ca. 700000 t of epoxy resins were used worldwide by the coating industry (including civil engineering applications). 

Polyurethane pressure-sensitive adhesives began appearing in the early 1970s [15]. By 1978 advanced two-component automotive structural adhesives (Goodyear) were commercially available. Waterborne polyurethane adhesives received additional attention during this period [16]. In 1984, Bostik developed reactive hot-melt adhesives [17]. Polyurethane adhesives are sold into an ever-widening array of markets and products, where they are known for their excellent adhesion, flexibility, low-temperature... 

Dehydrated castor oil and castor fatty acids are used in coatings and provide the following characteristics adhesion flexibility water, chemical, and abrasion resistance light colors and color retention. Important usage continues in the basic alkyl, epoxy, and acrylic film-forming polymer systems. 

PROPERTIES OF SPECIAL INTEREST Rapid drying. Good adhesion. Flexibility. Mar resistance and durability. Ester groups can be hydrolyzed under alkaline conditions. 

Features Tetrafunctional fast cure good adhesion, flexibility exc. pig-ment/substrate wetting Regulatory EINECS, CEPA listed... 

CAS 2676145-5 EINECS/ELINCS 247-979-2 Uses Reactive diluent for epoxy resins in ambient-cured heavy-duty industrial coatings, automotive OEM and refinish Features Significantly reduces need for soivs. improves adhesion, flexibility, durability, resistance to impact, chem. and salt spray produces reduced-VOC coatings... 

Uses PU intermediate for adhesives, flexible coatings, and castable elastomers... 

Chem. Descrip Trifunctional aliphatic urethane acrylate Uses Film-former for UV/EB-curable coatings and inks (plastics, packaging, wood), clear overprint vanishes Features Imparts exc. props, of adhesion, flexibility, and hardness Properties Pale yel. clear liq. m.w. 4,800 dens. 9.0 Ib/gal vise. 25,000-50,000 mPas ref. index 1.49 (20 C)... 

Features Enhances gloss, clarity, flexibility, and str. props, of hot-melt coatings can produce adhesives with exc. tackiness, adhesion, flexibility, and stability... 

Features Can produce adhesives with exc. tackiness, adhesion, flexibility, and stability... 

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