Tris- plasticizer

The history of plasticizers for man-made resins goes back to 18A6 when Schoenbein prepared cellulose nitrate, which provided the technology to make a resin that was amenable to plasticization (2). It was first plasticized by Alexander Parkes when he made "Parkesine," the forerunner of Celluloid (3 ). Parkes went on to produce various articles of plasticized cellulose nitrate. To modify their flexibility and hardness, he tried plasticizing the resin with oils, gums, paraffins, stearine, tar, glycerine, and other substances and varied proportions of those to his "pyroxy1ine." Cottonseed or castor oils were the preferred plasticizers cited in his master patent issued in 1865. 

While I was tempted to use thin steel plate for the dam, I elected to first try plastic material. Why With prototypes, it s best to build fast and... 

Tris(2-ethylhexyl) phosphate shows good compatibiUty with PVC and also imparts good low temperature performance in addition to good fire retardancy. 2-Ethyhexyl diphenyl phosphate has widespread use in dexible PVC appHcations due to its combination of properties of plasticizing efficiency, low temperature performance, migration resistance, and fire retardancy. 

Antimony tris(isooctylthioglycolate) has found use in pipe formulations at low levels. Its disadvantage is that it cross-stains with sulfide-based tin stabilizers (122). Barium—zinc stabilizers have found use in plasticized compounds, replacing barium—cadmium stabilizers. These are used in mol dings, profiles, and wire coatings. Cadmium use has decreased because of environmental concerns surrounding certain heavy metals. 

Citric acid esters are used as plasticizers ia plastics such as poly(viayl chloride), poly(vinhdene chloride), poly(viQyl acetate), poly(viQyl butyral), polypropylene, chlorinated rubber, ethylceUulose, and cellulose nitrate. Most citrate esters are nontoxic and are acceptable by the FDA for use in food-contact packaging and for flavor in certain foods. As a plasticizer, citrate esters provide good heat and light stabiUty and excellent flexibiUty at low temperatures. Triethyl citrate, tri- -butyl citrate, isopropyl citrate, and stearyl citrate are considered GRAS for use as food ingredients (224—228). 

Phosphoms oxychloride reacts with ethylene oxide in the presence of aluminum chloride to give tris-2-chloroethyl phosphate, a valuable plasticizer (75). Phosgene reacts with ethylene oxide and other alkylene oxides to form esters of chlorocarbonic acid (76) (see Carbonic and carbonochloridic esters). 

In 1862 the Great International Exhibition was held in London and was visited by six million people. At this exhibition a bronze medal was awarded to Parkes for his exhibit Ptu kesine. This was obtained by first preparing a suitable cellulose nitrate and dissolving it in a minimum of solvent. The mixture was then put on a heated rolling machine, from which some of the solvent was then removed. While still in the plastic state the material was then shaped by dies or pressure . In 1866 the Parkesine Co., Ltd was formed but it failed in 1868. This appears in part due to the fact that in trying to reduce production costs products inferior to... 

Although it is very difficult and probably of little value to produce an adequate definition of the word plastics , it is profitable to consider the chemical structure of known plastics materials and try to see if they have any features in common. 

It is probably most useful to consider toughness as a property of a plastics part under some specified conditions of service. Whilst it is possible to devise impact tests and to rank a series of plastics materials according to the results obtained in such tests it remains almost impossible to use such tests to try to predict whether or not an article made from a specific material will or will not be satisfactory in service. 

Since the last edition several new materials have been aimounced. Many of these are based on metallocene catalyst technology. Besides the more obvious materials such as metallocene-catalysed polyethylene and polypropylene these also include syndiotactic polystyrenes, ethylene-styrene copolymers and cycloolefin polymers. Developments also continue with condensation polymers with several new polyester-type materials of interest for bottle-blowing and/or degradable plastics. New phenolic-type resins have also been announced. As with previous editions I have tried to explain the properties of these new materials in terms of their structure and morphology involving the principles laid down in the earlier chapters. 

The morphology of a typical urethane adhesive was previously shown in Fig. 3. The continuous phase usually comprises the largest part of the adhesive, and the adhesion characteristics of the urethane are usually controlled by this phase. From a chemical standpoint, this continuous phase is usually comprised of the polyol and the small amount of isocyanate needed to react the polyol chain ends. A wide variety of polyols is commercially available. A few of the polyols most commonly used in urethane adhesives are shown in Table 2. As a first approximation, assuming a properly prepared bonding surface, it is wise to try to match the solubility parameters of the continuous phase with that of the substrate to be bonded. The adhesion properties of the urethane are controlled to a great extent by the continuous phase. Adhesion to medium polarity plastics, such as... 

Figure 9-6V. Jaeger Tri-Packs high-performance packing fabricated of corrosion resistant plastic. Used by permission of Jaeger Products, Inc.

One factor that has done a great deal to harm the reputation of plastics is that in many cases designers and engineers have, after deciding tentatively to try to introduce plastics, then lavishly copied the metal product it was to replace. Too much emphasis cannot be given to the general principle that plastics are to be used based on their behavior... 

Nauchoff s Explosives. Low freezing plastic expls patented prior to WW1 by S.A.S. Nauchoff of Sweden. It was claimed that they were equal to Dynamites in performance. Examples are (1) Liq TNT (gelatinized by dissolving 4p of NC in 96p of liq TNT, called flussige Tri in German) 31, Amm perchlorate 43 ... 

Kogut, L. and Etsion, I., A Static Eriction Model for Elastic-Plastic Contacting Rough Surfaces," Trans. ASME, J. Tri-bol, Vol. 126,2004, pp. 34- 0. 

FIGURE 10.13 Basic mechanism of dielectric elastomer actuator (DEA) generator. (From Kombluh, R., Power from plastic How electroactive polymer artificial muscles will improve portable power generator in tbe 21st century military, Presented at TRI-Service Power Expo, Norfolk, Virginia, July 2003. With permission.)... 

---