Neoprene WRT

Neoprene WRT, extremely low rate of crystallization Neoprene W, medium rate of erystal-lization Neoprene WHV, fast rate of crystallization Neoprene AD30, extremely fast rate of erystallization. 

Another possible explanation may be Increasing solubility of DI water In these Neoprene formulations, due, of course, to the additives. Other studies carried out at 5, 25 and 5O C over 24-40 day terms have shown that fresh water continues to be absorbed by Neoprene WRT without reaching equilibrium (vide Infra). Because permeability Is dependent on solubility, a continuing Increase In the latter will affect the former similarly. 

Features High vise, form of Neoprene WRT used for max. crystallization resistance and low-temp, flexibility... 

Regulatory FDA 21CFR 175.300,177.2600 Manuf/Distrib. ABCR Acros Org. Aldrich CarboMer Trade Names Baypren Latex B Baypren Latex GK Baypren Latex L 200A Baypren Latex L 345 Baypren Latex MKB Baypren Latex SK Baypren Latex T Neoprene Series Neoprene AC Neoprene AD Neoprene AG Neoprene GNA Neoprene GRT Neoprene GW Neoprene Liq. Disp. 115 Neoprene Liq. Disp. 622 Neoprene Liq. Disp. 654 Neoprene Liq. Disp. 671A Neoprene Liq. Disp. 735A Neoprene Liq. Disp. 842A Neoprene TRT Neoprene TW Neoprene W Neoprene WB Neoprene WD Neoprene WHV Neoprene WHV-100 Neoprene WHVA Neoprene WRT Trade Names Containing Baypren Latex 4 R... 

Neoprene TRT Neoprene TW Neoprene W Neoprene WB Neoprene WD Neoprene WHV Neoprene WHV-100 Neoprene WHVA Neoprene WRT polychloroprene, sealants Neoprene Series Neoprene AC Neoprene AD Neoprene AG Neoprene GNA Neoprene GRT Neoprene GW ... 

Neoprene WK f[DuPont http //www.dupont.com]] Neoprene WRT [DuPont Dow Elastomers http //www.dupont-dow.com] R.T. Vanderbilt http //www.rtvanderbiit.com]] Nobestos/D-7102 t[Lydall http //www.iydaii.com]] NPR 3911 t[DuPont http //www.dupont.com]] NPR 5587 i[DuPont http //www.dupont.com] Rhenoblend C 150 t[Rhein Chemie http //www.rheinchemie.com]] Skyprene B-5, B-10 [Tosoh http //www.tosoh.co.jp]] Skyprene B-30, B-31 [Tosoh http //www.tosoh.co.jp]] Skyprene E-20 [Tosoh http //www.tosoh.co.jp]] Skyprene E-33, Y-20E [Tosoh http //www.tosoh.co.jp]... 

Neoprene WRT grade Light calcined magnesia Phenyl-a-naphthylamine Tri-tolyl phosphate Paraffin wax Zinc oxide... 

Neoprene WRT, GRT Copolymers with 2,3-dichloro-l, 3-butadiene" with reduced linearity in the polymer chain thus reducing the tendency of the homopolymer to crystallise rapidly. 

Neoprene Type TW was shown to have low oral toxicity in rats. The LD q was found to be in excess of 20,000 mg/kg. Human patch tests with Types GN, W, WRT, and WHV showed no skin reactions (169). The FDA status of Du Pont Neoprene polymers is described (172). Although polychloroprene itself has not been shown to have potential health problems, it should be understood that many mbber chemicals that may be used with CR can be dangerous if not handled properly. This is particularly tme of ethylenethiourea curatives and, perhaps, secondary amine precursors often contained in sulfur modified polychloroprene types. Material safety data sheets should be consulted for specific information on products to be handled. 

Figure 3 Illustrates the change of solubility of water in WRT Neoprene with temperature. The solubilities of both deionized and 3.5% salt water were measured at 5, 25 and 50°C. The figure shows that DI water is more soluble than salt water in WRT Neoprene and that increasing temperature Increases solubility. The solubility of DI water at 50°C does not approach equilibrium even after 25 days. From these data a total weight gain of 300% was predicted.

Several elastomers were evaluated for permeability to salt and deionized water at several temperatures. A WRT Neoprene (Burke Rubber Co. Type 5109) was tested at 23, 40 and 70°C using both salt water (3.5%) and DI water as permeants. The results for salt water are listed In Table III and for DI water In Table IV. Salt water permeability Increased 24 times with a 47°C temperature rise while the DI water Increase was 33 times. The difference may be due to the much greater solubility of DI water relative to salt water. 

Experiments were run to evaluate the effects of low level static (stretch) and dynamic (ultrasonic Irradiation) stress on water permeation of a WRT Neoprene. At the same time, the contribution of a partial silica filler In the place of black was determined. The materials were Identical zinc oxlde-magne-slum oxide-cured formulations except that one contained 30 phr black and the other contained 15 phr black and 15 phr silica. These were molded Into cups with 0.030 In. thick faces and 0.070 In. thick side walls which were then fitted over 3.5X salt water-filled glass cups and sealed with hose clamps. 

Acceleration by ethylene thiourea is more effective with W- and WRT- based compounds than the G types. The neoprene G type compound is cheaper and inferior in abrasion, heat resistance and low temperature properties. 

WRT Similar to Neoprene W but with very slow rate 1.25 Very slow 41-51 ... 

Neoprene T-types Contain medium levels of gel and are superior processing versions of Neoprene W, WHV 100 and WRT but possess equivalent physical properties. 

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