Cyanoacrylates polycarbonate

All of the eommereial alkyl eyanoaerylate monomers are low-viseosity liquids, and for some applications this can be an advantage. However, there are instances where a viseous liquid or a gel adhesive would be preferred, sueh as for application to a vertical surface or on porous substrates. A variety of viscosity control agents, depending upon the desired properties, have been added to increase the viscosity of instant adhesives [21]. The materials, which have been utilized, include polymethyl methacrylate, hydrophobic silica, hydrophobic alumina, treated quartz, polyethyl cyanoacrylate, cellulose esters, polycarbonates, and carbon black. For example, the addition of 5-10% of amorphous, non-crystalline, fumed silica to ethyl cyanoacrylate changes the monomer viscosity from a 2-cps liquid to a gelled material [22]. Because of the sensitivity of cyanoacrylate esters to basic materials, some additives require treatment with an acid to prevent premature gelation of the product. 

Polycarbonate Conventional adhesives recommended include epoxies, modified epoxies, polyurethanes, acrylics, RTV silicones, cyanoacrylates, one-part elastomers, some epoxy-polyamides, and hot melts (13). 

Ethyl cyanoacrylate is a little less polar than methyl cyanoacrylate, and has the ability to wet plastic surfaces more readily, and is a better solvent for plastics. With this added ability to make intimate contact with the surface, the bonds on plastic are stronger with ethyl cyanoacrylate than with the methyl ester. This difference in performance gives rise to the adage that methyl is for metal and ethyl is for everything else. Sometimes this difference can be utilized in reverse to good advantage to avoid stress cracking on such sensitive plastics as polycarbonate and polyacrylate. 

In a more detailed investigation of the effect of moisture on cyanoacrylate-bonded steel joints. Drain et al. concluded that the loss of strength is due to the formation of an oxide layer at the adhesive-metal interface and possibly to concurrent surface hydrolysis of the polymer. The adhesive appears to be relatively impermeable to water which they suggest most likely enters the bondline by wicking along the interface. Polycarbonate joints exposed to the same aging conditions remained virtually unaffected. 

Thermoplastic polyesters include unfilled or reinforced grades of polycarbonates, polyethylene terephthalate, polybutylene terephthalate and blends and copolymers of these plastics. Cyanoacrylates and urethanes bond well to these materials. UV-cured acrylics are suitable for transparent plastics such as polycarbonate. 

In the automotive market, cyanoacrylates are used to bond weatherstripping to automotive bodies and to position rubber gaskets before assembly. They are used to bond polycarbonate positioning clips to side windows of automobiles, alternator horn assembly components, and rubber gaskets to automotive thermostats. One of the most common automotive applications is the use of cyanoacrylates in the repair of flexible PVC side trim strips. 

ITC) deposited on flexible, plastic substrates such as PMMA or polycarbonate was used as the conductive electrode substrate, with the active electrochromic electrodes producible as a roll which could be attached to window panes with common (e.g. cyanoacrylate) adhesives. This device again optionally used a counter electrode which was also electrochromic, with the difference that it could be not only a metal oxide such as WO3, but also, interestingly, an n-type CP, which of course displays electrochromism which is complementary to that of the more common p-type CPs. Thus, as cathode materials, the p-type CPs P(ANi) s, P(Py) s and poly(phenylene vinylene) were listed as usable, with virtually all the common dopants. As anode materials, WO3, M0O3, poly(isothianaphthene), and the -type CPs poly(alkoxy-thienylene vinylene) poly(p-phenylene), poly(phenyl quinoline) and poly(acetylene) were listed as usable. Liquid nonaqueous electrolytes based on common solvents such as DMSO and THF were used. No electrochromic data were however given in the patent or in subsequent publications. 

The ethyl cyanoacrylates are probably the most common of all the standard cyanoacrylates and the most widely used. The ethyl cyanoacrylates are best suited for bonding most plastics and elastomers to themselves and have excellent adhesion to polycarbonate, acrylonitrile butadiene styrene, poly(vinyl chloride) (PVC) and butyl rubber amongst many. 

On amorphous thermoplastics, however, such as acrylonitrile butadiene styrene (ABS) and polycarbonate, standard ethyl cyanoacrylates showed excellent bond-strength... 

Products obtained by pyrolysis of other polymers is reviewed in Table 4.5. Some specific applications of the chromatography-MS technique to various types of polymers include the following PE [34,35], poly(l-octene) [29], poly(l-decene) [29], poly(l-dodecene) [29], CPE [36], polyolefins [37, 38], acrylic acid-methacrylic acid copolymers [39, 40], polyacrylate [41], nitrile rubber [42], natural rubbers [43, 44], chlorinated natural rubber [45, 46], polychloroprene [47], PVC [48-50], polysilicones [51, 52, 53], polycarbonates [54], styrene-isoprene copolymers [55], substituted olystyrene [56], PP carbonate [57], ethylene-vinyl acetate [58], Nylon 66 [59], polyisopropenyl cyclohexane-a-methyl styrene copolymers [60], cresol-novolac epoxy resins [61], polymeric flame retardants [62], poly(4-N-alkyl styrenes) [63], polyvinyl pyrrolidone [64], polybutyl-cyanoacrylate [65], polysulfides [66], poly(diethyl-2-methacryl-oxy) ethyl phosphate [67, 68], polyetherimide [69], bisphenol-A [70], polybutadiene [71], polyacenaphthalene [72], poly(l-lactide) [73], polyesterimide [74], polyphenylene triazine [75], poly-4-N-vinyl pyridine [76], diglycidylether-bisphenol-A epoxy resins [77], polyvinylidene chloride [78] and poly-p-chloromethyl styrene [79]. 

---