Acrylic adhesives storage

Azuma, K. Kato, H. Tatsumichi, H. Storage-stable anaerobic acrylate adhesives. Jpn. Kokai Tokkyo Koho JP 52121090, 1977 Chem. Abstr. 1978, 88, 171340. 

There are two basic classes of adhesive bonding in aeronautical structures. One is structural bonding, with epoxy, phenolic, or acrylic adhesives, that transfer load between members. The other is sealants, to protect against corrosion at interfaces. The stifihesses of these classes of polymers differ greatly, but the two basic needs are remarkably. similar. The first is that the adhesive or sealant will stay stuck for the life of the structure, in aU service and storage environments, while the second is that the adhesive will not fail even when the surrounding structure has been broken. 

Sakamoto et al. (2) prepared macromonomers consisting of poly (butyl acrylate-/7-methyl methacrylate), which were used as paint additives to enhance adhesiveness and storage stability properties. 

Acrylic latex sealants. Adhesion strengths on three substrates after 3 months sealant storage (0.5% silane added) were evaluated and the results are presented in Table 4. 

The majority of adhesive laminations in multilayer flexible packaging are manufactured using the dry-bond process. In this technique, a liquid adhesive is applied to one substrate. The adhesive is then dried using hot air. This dried surface can be adhered to a second substrate using heat and pressure at a nip point. The adhesive formulations themselves represent a reactive chemistry (typically urethanes or acrylics) that is chosen to withstand the processing and storage/distribution environment of the filled product. The adhesives polymerise and/or cross-link during production of the laminated product. 

Cyanoacrylates are marketed as contact adhesives. Often popularly known as superglue, they have found numerous applications. In dry air and in the presence of polymerization inhibitors, methyl- and ethyl-2-cyanoacrylates have a storage life of many months. As with many acrylic monomers, air can inhibit or severely retard polymerization of cyanoacrylates. These monomers are, however, prone to anionic polymerization, and even a very weak base such as water can bring about rapid polymerization. 

Most of the water-soluble monomers, such as the acrylic and methacrylic acids, are functional monomers and are covered in Section 6.2.3. In Table 6.1 the most water-soluble monomers are acrylamide, acrylonitrile, methyl acrylate and vinyl acetate. Acrylamide contains two reactive centres. The amide group undergoes the reactions characteristic to aliphatic amides. For this reason, acrylamide may be considered as a functional monomer. Copolymerization of acrylamide with other monomers is often done to incorporate hydrophilic centres in oleophylic polymers to promote adhesion and dye acceptance. The monomer is available either as a solid or as a 50% aqueous solution. The latter is the preferred form, since it eliminates handling of a solid. The monomer is a neurotoxin and exposure to skin or inhalation must be prevented. Acrylamide solution is stabilized with cupric ions. Cupric ion availability is pH dependent and the pH must be between 5.2 and 6. Storage temperature should be between 16 and 32 °C... 

Properties Wh. cryst. powd. sol. in butyl acetate, isobornyl acrylate, dipropylene glycol diacrylate, hexanediol diactylate insol. in water m.w. 256 sp.gr. 1.17 m.p. 64-67 C 99% min. assay Use Level 1-3% (wood fillers, topcoats) 2-6% (printing inks) 1-1.5% (printing plates) 2-4% (laminating adhesives) 2-6% (photoresists) Storage Store below 30 C keep dry extended exposure to elevated temps, or visible light may reduce shelf life keep away from ignition sources... 

Chem. Desetp. Hexadecyl acrylate with MEHQ inhibitor (300 ppm) Uses Flexibilizer, adhesion promoter, water resistance aid in coatings, all radiation-curable formulations Features Good weatherabilily very low VOC Properties Gardner 3 max. clear liq. dens. 7.2 Ib/gal vise. 8-12 cps acid no. 0.5 max. sapon. no. 180-190 flash pt. > 200 F 0.5% max. moisture Storage Store in a cool, shaded, well ventilated area away from direct sources of heat and sunlight Photomer 4818 [Cognis/Coatings Inks]... 

Use Level 0.1-1% (syn. acrylic stucco) 0.2-1% (adhesives/caulks/sealants) 0.3-1% (exterior paints, wood stains) 0.5-2% (roof coatings) Storage Store tightly closed < 7 C Troysan Polyphase AF1 [Troy]... 

Storage Keep away from ignition sources Uses Polymer and copolymers in surgical adhesives, coalings, and lacquers acrylic resin comonomer in adhesives, textiles, leather, paper coalings plasticizer for nitrocellulose and other plastics modifier for alkyd and polystyrene resins chemical intermediate Manuf./Distrib. Aldrich BASF AG Fluka... 

Properties Liq. insol. in water m.w. 226.28 dens. 1.010 b.p. 290 C flash pt. (COC) 124 C ref. index 1.4520 Toxicology TSCA listed Storage Light-sensitive Uses Peroxide crosslinker/coactivator for elastomers, PVC plastisols, syn. resins, cast acrylic sheet/rods coagent for rubber compding. impregnant for metal and wood composites, adhesives, and glass-reinforced... 

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