Transparent resins

Some plastics tend to react with zinc to give an undeskable bubbling effect when molded. There is also a tendency to darken due to tarnishing by the action of sulfides. Tarnish-resistant bronzes are available in which the particles have been coated with a transparent resin (9). 

After washing the ether-benzene layer, the solvents are eliminated in vacuo and an ester-alcohol is thus obtained with a yield of 98%, in the form of a transparent resin. This resin, if treated with petroleum ether, yields 6.35 g of ester-alcohol in the form of fine needles (MP = 66.68°C) which are very soluble in the chief organic solvents and in petroleum ether. 

Epoxy resins have a wide range of molecular weights (=1,000-10,000). Those with higher molecular weights, termed phenoxy, are hydrolyzed to transparent resins that do not have the epoxide groups. These could he used in molding purposes, or crosslinked hy diisocyanates or hy cyclic anhydrides. 

High molecular weight thermoplastics called phenoxy resins are formed by the hydrolysis of the epoxy resins so that no epoxy groups are present. These transparent resins can be further reacted, forming cross-linked material through reaction of the hydroxyl pendant groups with diisocyanates or cyclic anhydrides. 

Polyacrylic acid and polymcthacrylic acid and their sodium salts are water-soluble. Copolymers with small amounts of methacrylic add and ethylene (ionomers), are moldable transparent resins. 

Transparent resins are used as the materials for molded products, such as automobile components, illumination equipment, and electrical components. Transparent resins, which can be applied to such applications, include poly(carbonate) (PC)-based resins and acrylic-based resins. 

In the UV-range it shows a better transmission compared with glass or other transparent resins. Due these properties, TPX can be used for cells in spectroscopy. 

The proximate principles of elemi are a transparent resin having acid properties, soluble in cold alcohol a second rosin taken up by boiling alcohol, bat deposited from the solution on eoolingin a crystalline state , a volatile colorless oil, which, according to Deville, resembles much the essence of turpentine, and of citron in composition, as in its reactions and a bitter extractive. The annexed per centages wore found by BoNAsrnE —... 

Blends of iso- and terephthalates give amorphous, transparent resins, mosdy yellow in color. Heat-deflection temperatures are higher than those of 100% PC resins and depend on the iso- to terephthalate ratio. For example, a resin with a 1 1 ratio has a value of 160°C. These resins are flame retardant mechanical and electrical properties are similar to those of PC resins. The notched Izod impacts are lower at 150—300 J/m (4.7—5.6 fflbf/in.), even in thick sections. Long-term uv radiation stabilities are excellent, but yellowness increases during initial exposure owing to photo-Fries rearrangements (80), wherein 0-hydroxy-benzophenone units are produced along the polymer chains. 

CHOH.(CHOH)2.CH2, (CHOH)2 mw 164.16 monoclinic crysts with a sweet taste mp 234— 35° sol in w si sol in hot, almost insol in cold ale practically insol in eth. Found in the acoms of various species of Quercus Fagaceae (Refs 2, 3 6). Its structure was detd by Kiliani (Ref 7), Postemak (Ref 8), and others (Ref 1, p [1151]). On nitration, it forms an expl compd Quercitol Pentenitrate (Nitroquercite). C6H7(0N02)s, mw 389.16, N 18.00%, OB to CO —2.1% nearly colorl, transparent, resinous substance mp, explds... 

Pearlescent pigments can also be used in plastic formulations to produce mar-bleized and frosted effects. Marble effects using pearlescent pigments show the typical crystalline lattice structure of natural marble and make the effect appear more real in plastics. The effect known as the frost effect is easily produced while using the pearlescent pigments at very low loading levels (0.2%) in the transparent resin system. 

As mentioned in the last section, three types of fluorinated pitches, yellowish white powdery solid (S-type), colorless transparent resin (R-type) and liquid (L-type),... 

Heat treatment of the S-type fluoride in a fluorine atmosphere Based on the results above mentioned, Fujimoto et al. developed a new fluorination procedure in order to prepare the perfluorinated pitch, and obtained two types of other fluorinated pitches [23,24], The new process is by the heat treatment at 200-400°C of S-type of fluorinated pitch prepared at relatively low temperature in a fluorine atmosphere. They firstly fluorinated the mesophase pitch at 70°C for 10 h (first step for the preparation of S-type fluorinated pitch) and then heated up to a selected temperature between 200°C and 400°C, and maintained this temperature for 12 h (second step for the heat-treatment of fluorinated pitch). Thus, they obtained two kinds of fluorocarbons, a transparent resin (R-type) and a liquid (L-type). L-type is a viscous fluid containing some volatile materials and the viscosity gradually becomes higher when it is kept for a few weeks in an air atmosphere even at ambient temperature. They reported that the R-type was obtained in the nickel boat in the heating zone and L-type at the bottom of the vertical reaction vessel which was cooled down by the water. Therefore, it is likely that the liquid fluorocarbon is formed by the vaporization of some component contained in the S-type fluoride or decomposition reaction during the heat treatment of the S-type fluoride. The yields of these compounds depends on the heat treatment temperature. In Fig. 3, the yields of the R-type and L-type fluorocarbons are plotted as a function of the heat treatment temperature of the S-type fluoride. The yield of the former decreases with increase of the heat treatment temperature and finally, at 400 C, it can not be obtained at all. On the other hand, the yield of the latter increases with increase of temperature and it is selectively obtained at 400°C. 

Thermoplastic resin compositions consisting of ethylene, propylene, 5-ethylidene-2-norborene, and trimethylsilyl 4-methyl-tetracyclo[6.2.1.1 . 0 ]-dodec-9-ene -carboxylate were prepared and hydrolyzed into the corresponding carboxylic acid. These materials are useful as transparent resins in automotive components. 

It is very rich in inclusions that are magnificently preserved, and are usually clearly visible in the transparent resin (Fig. 1.4). 

The resin is extracted fix>m the tree in much the same way as rubber. A cut is made in the tree trunk and the transparent resin pours into a little cup tied beneath the cut. As it comes into contact with the air, the resin becomes opaque and thickens. Before use it is boiled and filtered, and mineral pigments are added to give colour. Examples are cinnabar for bright red, or iron oxide for dark red. 

The acrylate resinoids are esters of acrylic and methacrylic acid. Methyl methacrylate, CH2 = C(CH3)COOH3, is a liquid ester which polymerizes to a transparent resin of high tensile strength. The polymerization is brought about by catalysts such as peroxides and heat. The polymerization is assumed to take place by addition to form linear molecules ... 

A) Preparation of Phenol-Formaldehyde Resin. Place in an eight-inch tube 5 g of phenol, 15 ml of 40 per cent formaldehyde solution, and 3 ml of concentrated aqueous ammonia. Heat the tube for a few minutes with a small flame until the solution becomes opaque and milky. Cool the tube, and decant the upper layer, retaining the lower viscous material. Add 10-12 drops of acetic acid to the viscous material and heat in a water bath at 60 for thirty minutes. Pour some of the liquid into a glass tube 6 mm in diameter and 100-150 mm in length, sealed at one end. Place the remainder in a small clean test tube made of thin glass. Label both tubes, and place in oven at 80° until the next laboratory period. Break the tubes cautiously to obtain the clear transparent resin. 

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