Adhesives polymerization

Classifying polymers in their crosslinked state according to end-use properties, polymer networks include vulcanized rubbers, crosslinked thermosetting materials, protective coatings, adhesives, polymeric sorbents, microelectronics materials, soft gels, etc. Polymer networks in contrast to uncrosslinked polymers,... 

Gel. A jelly-like substance formed as solutes (materials in solution) from submicroscopic crystalline particle groups that capture much or all of the solvent in their interstices or structure. Usually, the solutes are a small proportion, maybe 1-2% of the gel. Gels can be used for filters and clarifying agents, textile and paper adhesives, polymerization precursors, and of course, as a component in gelatin the Italian ice cream. 

Laminating Adhesives Polymeric Fiber-Reinforced Composites... 

The main applications for PVA are in textile sizing, adhesives, polymerization stabilizers, paper coating, poly(vinyl butyial), and PVA fibers. In terms of percentage, and omitting the production of PVA not isolated prior to conversion into poly(vinyl butyral), the principal applications are textile sizes, at 30% adhesives, including use as a protective colloid, at 25% fibers, at 15% paper sizes, at 15%, poly(vinyl butyral), at 10% and others, at 5%, which include water-soluble films, nonwoven fabric binders, thickeners, slow-release binders for fertilizer, photoprinting plates, sponges for cosmetic, and health care applications. 

As the continuous ribbon is conveyed from the forming station it may or may not be consolidated by a cold press. This prepressing operation reduces the mat thickness and increases the mat density which improves the handling characteristics of the mat, but does not initiate adhesive polymerization. The continuous ribbon is also trimmed to width and cut into individual mats, the length of which is equal to the length of the hot press. The individual mats are placed in the press loader which serves as a temporary storage area for the mats prior to hot pressing. 

It is made by dimerizing cyanamide in basic aqueous solution, and is a colorless solid melting at 208°C. Dicyandiamide is soluble in polar solvents, but at room temperature is insoluble in bisphenol A epoxy resins. It can be made into a very fine powder and milled into epoxy resins to form stable dispersions. Because the dicy is insoluble in the epoxy, the only possible reaction sites are at the particle surfaces. Although some reaction certainly occurs over a short time, the adhesives easily can have a useful shelf life of six months. On heating to about 150°C, the dicyandiamide becomes soluble in the epoxy resin, and the adhesive polymerizes rapidly. Cure can be accelerated by incorporation of tertiary aromatic amines or substituted ureas. 

Yoo, J. W., Dharmala, K., and Lee, C. H. (2006),The physicodynamic properties of muco-adhesive polymeric films developed as female controlled drug delivery system, Int. J. Pharm., 309,139-145. 

Dresinate . [Hercules Hercules BV] Rosin so emulsifier, pigment wetting agent, dispersant, foaming agent, stabilizer for adhesives, polymerization, metalworiting, drilling muds, asphalt, industrial and househdd ctean-ers. 

Infrared analysis of adhesive samples representing various percent conversion was achieved using reflectance spectroscopy. The transmission mode was Ineffective due to sample thickness and opacity. Limitation of the reflectance technique for measurement of bulk adhesive polymerization was apparent on examination of the sample surface nearest the UV source which Indicates complete cure (Irrespective of Irradiation time for t >0 sec). Consequently, the sample surface furthest from the UV source was used to Indicate conversion. Area ratio of absorption bands at 830 and 810 cm was calculated for this determination. The 810 cm band Intensity, attributable to CH2 deformation of carbon double bond functionality. Is directly proportional to conversion. Spectra of samples representing O-IOOZ conversion are shown In Figure 4. 

Chem. Descrip. Proprietary polysiloxane-based defoamer in wh. spirit Uses Defoamer for nonaq. high-solids and waterborne epoxy coatings, alkyds, acrylics, PU, polyester, disp. adhesives, polymerization Regulatory DOT regulated SARA 311/312 reportable Properties Yel. clear liq. aromatic odor negligible sol. in water sp.gr. 0.80 dens. 6.7 Ib/gal vise. 15 cps flash pt. (PMCC) 55 C VOC 74.2% (EPA method 24) 100% act., 20.6% solids Use Level 0.2-1.0% on total wt. 

CAS 3006-15-3 EINECS/ELINCS 221-109-1 Uses Wetting agent, emulsifier tor waterborne industrial coalings (PVAc, acrylics), printing inks, aq. adhesives, polymerization, cleaners, wallpaper removers adhesion promoter tor ditlicult-to-wet substrates, e.g., water-lhinnable overprint varnishes tor otiset printing Properties Gardner 2 color dens. 9.5 Ib/gal vise. 800 cps VOC 4.2% (EPA Method 24) anionic 80% act., 80% solids, 15.8% water Use Level 0.1-1.0% on total wt. 

Uses Emulsifier, flow aid, anticratering agent for polymer emulsions, waterborne industrial coatings (epoxy, alkyds, polyesters), emulsion printing inks, aq. adhesives, polymerization, cleaners, wallpaper removers Features Silicone-free... 

Uses Inks paint and varnish driers catalyst anodizing mineral supplement in feed additives foam stabilizer in food-pkg. adhesives polymerization catalyst in mfg. of paper/paperboard in contact with aq./ fatty foods catalyst for curing urethanes, epoxies additive in fuels, lubricants crosslinking reflective and conductive coatings on glass or other substrates... 

The information presented in this section demonstrates that the conditions of wetting of the substrate by the adhesive (which is the first and most important stage of formation of an adhesive-bonded joint), determined by the adhesive s surface tension, depend not only on the type of sm-factant and its concentration but also on the change in the surfactant structure in the com-se of the adhesive polymerization. 

The properties of the system change in the course of IPN formation both the modulus of elasticity (Table 4.2) and the adhesion strength (Fig. 4.9) increase. The adhesion strength of IPN exceeds that with polyester or polyurethane adhesive. One reason is the low level of the internal stresses in the adhesive layer of IPN compared with polyester (Fig. 4.10). The decrease of the internal stresses in this case is explained by the increased rate of relaxation of the internal stresses in the adhesive layer due to the presence of a substantial amount of liquid MDI. Because polymerization of MDI runs for a long time, the internal stresses manage to relax completely even 100 days after the adhesive polymerization, the stresses do not exceed 1—1.5 MPa. 

In experiments on rabbits and dogs, a method was worked out for closing colonic fistulas with the KL-3 adhesive [439] as follows. A pol5winyl chloride probe with 1—1.5 ml of the adhesive at its end is drawn into the fistula canal. Then the probe is gradually drawn out and simultaneously the adhesive fills the fistula canal, being pressurized by means of a syringe. Adhesive polymerization occurs immediately in the fistula canal. 

Formula (CH3)2CH0C(0)00C(0)0CH(CH3)2 Properties Colorless cryst. solid or liq. misc. with aliphatic, aromatic, and chlorinated hydrocarbons, esters, ethers pract. insol. in water m.w. 206.22 dens. 1.080 (15.5/4 C) m.p. 8-10 C rapid decomp. 63 F ref. index 1.4034 (20 C) Toxicology LD50 (oral, rat) 2140 mg/kg, (skin, rabbit) 2025 mg/kg mod. toxic by ing. and skin contact primary severe eye irritant TSCA listed Precaution Dangerous fire risk unstable above IOC impact- and heat-sensitive explosive spontaneous decomp. R.T. releases flamm. and corrosive prods. explodes on heating explodes on contact with amines or potassium iodide, possibly organics Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and fumes NFPA Health 0, Flammability 4, Reactivity 4 Storage Store in open containers low temps, with adequate ventilation Uses Low-temp, polymerization catalyst initiator for polymerization of unsat. monomers, PVC in food-pkg. adhesives polymerization catalyst in mfg. of paper/paperboard in contact with aq./fatty foods... 

Glyceryl-1-allyl ether PU solid elastomer mfg. 1,5-Naphthalene diisocyanate PU, adhesives Polymeric MDI PU, appliances Polymeric MDI PU, automotive... 

---