Tack-free films

International Specialty Products (ISP) suppHes ethyl, isopropyl, and -butyl half-esters of PMVEMA as 50% solutions in ethanol or 2-propanol. Typical properties are shown in Table 8. These half-esters do not dissolve in water but are soluble in dilute aqueous alkaU and in aqueous alcohoHc amine solutions. The main appHcation for the half-esters is in hairsprays where they combine excellent hair-holding properties at high humidity without making the hair stiff or harsh. These half-esters are easily removed during shampooing, have a very low order of toxicity, and form tack-free films that exhibit good gloss, luster, and sheen (see Hair preparations). 

It clearly shows that the polymerization reaction proceeds at a low rate at room temperature. Although it is possible to obtain tack-free films by irradiation, the sample should be heated subsequently in order to complete the polymerization of the available epoxy groups within a reasonable period of time. 

Forms firm, tack-free films. Recommended for fabric finishing and backcoating. 

Durability to Washing Excellent Durability to Drycleaning Good Forms a hard, tack-free film that does not discolor when subjected to high temperatures. Excellent mechanical stability. Especially recommended for spray bonding fiberfill that subsequently will be molded. 

Figure 10. Maximum rate of cure that gave thumb-twist-free and tack-free films (56)...

Figure 9. Variation of log rate of cure Figure 10. Maximum rate of cure that with log relative intensity of ultraviolet gave thumb-twist-free and tack-free films light irradiation (56) (56)...

UP Resins for Fillers. Tack-free films are also obtained if phthalic acid anhydride is substituted with tetrahydrophthalic acid anhydride [2.104]. The addition of en-domethyl tetrahydrophthalic acid anhydride (a cycloaddition product of maleic acid and cyclopentadiene) also has a positive effect on the air-drying properties [2.105]. Both product classes have become popular above all in the manufacture of binders for highly extended fillers for vehicle repair applications. 

Features Med. reactivity good yeiiowing resist. cures gives tack-free films high humidity... 

Chem. Descrip. Calcium sulfonate/carbonate complex in mineral spirits Uses Corrosion inhibitor in aerospace, asphalt, automotive (body and frame, sheet steel), oil field, small parts, storage coatings, tubular steel Features Sprayable provides firm, waxy, tack-free films Properties Brn. color dens. 8.2-8.5 Ib/gal vise. 10,000-25,000 cps flash pt. (PMCC)>105 F 68-73% solids SACI 8100 [Stoney Creek Tech. Sea-Land]... 

If the mole ratio of PA to glycerol were 2 to 3, 5 mol of soybean fatty acid could be esterified to 5ueld an alkyd with an of 3.45. This alkyd would cross-link more rapidly than the 1 2 4 mole ratio alkyd and would also form tack-free films even faster because the ratio of aromatic rings to long aliphatic chains would be 2 5 instead of 1 4. As the ratio of PA to glycerol is increased further, the average... 

After condensation to a resin, the mixture is made up to 70% solids in mineral spirits. The solution dries in 30 hr to a tack-free film. 

Use of dibutyltin diacrylate and its diisobutyl or dioctyl analogs in electron-beam polymerization to form tack-free films [147]. 

A typical formulation for the production of photoembossed stmctures contains a polymer base material, a polyfunctional monomer, a photoinitiator, and, optionally, a thermal initiator. For the coating process, solvents are added. The blend is composed so that after evaporation of the solvent a solid, tack-free film is formed, al-... 

Another way of automating assembly is to use the epoxy adhesive in the front of a silver filled or oxide filled tape. These tapes are made by impregnating the epoxy adhesive into a glass mesh support, B-staging to form a tack-free film, and then slitting the tape into rolls or diecutting the tape into custom-made preforms. In production, the user places a preform under the part to be bonded, or uses a machine to chop or punch preforms from a roll of tape. In either case, the tape provides precise control of bond thickness, eliminates voids, and avoids an excessive fillet. The tapes can be cured very quickly, at temperatures over 160°C, and the controlled thickness of the bond reduces thermal stresses due to thermal expansion mismatch between bonded part and the substrate. 

The free-standing films were made by casting DMAc solutions of the poly(amic acid)s onto a dust-free glass plate and vacuum drying at ambient temperature until tack-free. Films were cured under a dynamic nitrogen atmosphere at 30 C for 0.5 h and at 100,200, 300 C each for 1 h. In situ FTIR spectra (using a heated IR cell) confirmed the cyclization process. Disappearance of peaks at ca 1220 and 1544 cm were diagnostic for reaction of the amide and add residues while appearance of new peaks at ca 1365 and 1775 cm confirmed imide formation. 

Features Forms highly polar, tack-free films dispersant, coupling, stabilizing props. 

Uses Solubilizer, emollient, conditioner, cleanser, superfatting agent, foam stabilizer, and lubricant for alcoholic and aq. compositions, topical pharmaceuticals plasticizer for hair sprays o/w emulsifier solubilizers Features Forms glossy, tack-free films Regulatory Japanese approved... 

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