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Styrenics consumption

Ethylbenzene is to styrene what cumene is to phenol. The only reason you want to make ethylbenzene is so you can malce styrene. Its destiny is tied to styrene consumption. Most ethylbenzene (EB) is made by alkylating benzene with ethylene, as shown in Figure 8—1. [Pg.119]

Figure I. Finemann-Ross plot of styrene-Tetralin co-oxidations in Table II. The symbol X indicates the results if styrene consumption were 1.5% greater or less than shown in Table II... Figure I. Finemann-Ross plot of styrene-Tetralin co-oxidations in Table II. The symbol X indicates the results if styrene consumption were 1.5% greater or less than shown in Table II...
The determination of the evolution of concentrations of different species and functional groups enables one to discern different paths present in the reaction mechanism. For example, Fig. 5.13 shows that as the molar ratio of styrene to polyester C=C double bonds (MR) increases from 1/1 to 4/1, the curves tend to shift downward. For MR = 4/1 there is a very low styrene consumption until the polyester double bonds are converted to 40%. On the other hand, SEM (scanning electron microscopy) shows phase separation of a UP-rich phase in the early stages of the polymerization. Most radicals are probably trapped in this phase, which explains the higher initial conversion of the UP double bonds than styrene double bonds. A kinetic model would have to take this observation into account. [Pg.183]

Fig. 2a. Dependence of rate of styrene consumption on weight of 13 X zeolite l... Fig. 2a. Dependence of rate of styrene consumption on weight of 13 X zeolite l...
Interesting phenomena are observed in this copolymerization if one looks beyond the initialization period. In the case of cumyl as the leaving group, exclusive addition to maleic anhydride takes place. Maleic anhydride does not undergo homopropagation, which means that after initialization styrene consumption starts, whereas the maleic anhydride consumption rate reduces to virtually zero. The behaviour visually resembles a second initialization, but the... [Pg.156]

The proportion of styrene grafted onto polybutadiene is controlled by the ratio of rubber to styrene in the reaction mixture. The cis and trans isomers of polybutadiene have equal activity. Normal first-order kinetics for styrene consumption were observed, and the molecular weight dependence on monomer and initiator concentrations were as expected. Through careful separation, a decrease in the molecular weight of the ungrafted rubber was noted. [Pg.1208]

Thermal Oxidative Stability. ABS undergoes autoxidation and the kinetic features of the oxygen consumption reaction are consistent with an autocatalytic free-radical chain mechanism. Comparisons of the rate of oxidation of ABS with that of polybutadiene and styrene—acrylonitrile copolymer indicate that the polybutadiene component is significantly more sensitive to oxidation than the thermoplastic component (31—33). Oxidation of polybutadiene under these conditions results in embrittlement of the mbber because of cross-linking such embrittlement of the elastomer in ABS results in the loss of impact resistance. Studies have also indicated that oxidation causes detachment of the grafted styrene—acrylonitrile copolymer from the elastomer which contributes to impact deterioration (34). [Pg.203]

Automotive appHcations account for about 116,000 t of woddwide consumption aimuaHy, with appHcations for various components including headlamp assembHes, interior instmment panels, bumpers, etc. Many automotive appHcations use blends of polycarbonate with acrylonitrile—butadiene—styrene (ABS) or with poly(butylene terephthalate) (PBT) (see Acrylonitrile polymers). Both large and smaH appHances also account for large markets for polycarbonate. Consumption is about 54,000 t aimuaHy. Polycarbonate is attractive to use in light appHances, including houseware items and power tools, because of its heat resistance and good electrical properties, combined with superior impact resistance. [Pg.285]

In 1990, the annual U.S. capacity to manufacture styrene monomer was 4,273,000 t/yr, and production was 3,636,000 t/yr (11). Polystyrene resin is the dominant user of styrene monomer. SBR use is about 7% of U.S. domestic styrene monomer production. Woddwide production in 1995 was projected to be 77% of capacity as demand increased just under 5% per year, from 1990 consumption of 13,771,000 to 17,000,000 metric tons in 1995. [Pg.494]

Styrene—butadiene elastomers, emulsion and solution types combined, are reported to be the largest-volume synthetic mbber, with 28.7% of the world consumption of all synthetic mbber in 1994 (38). This percentage has decreased steadily since 1973 when SBR s market share was 57% (39). The decline has been attributed to the switch to radial tires (longer milage) and the growth of other synthetic polymers, such as polyethylene, polypropylene, polyester, and polystyrene. Since 1985, production of SBR has been flat (Table 3). [Pg.499]

Estimates of benzene consumption for nonfuel uses are shown iu Table 13 (135). Benzene consumption worldwide is dominated by the production of three main derivatives, styrene, cumene, and cyclohexane, which account for nearly 90% of the total. [Pg.48]

Benzene is alkylated with ethylene to produce ethylbenzene, which is then dehydrogenated to styrene, the most important chemical iatermediate derived from benzene. Styrene is a raw material for the production of polystyrene and styrene copolymers such as ABS and SAN. Ethylbenzene accounted for nearly 52% of benzene consumption ia 1988. [Pg.48]

Fig. 7. U.S. production and consumption of styrene block copolymers (104). A, Total production B, consumption C, adhesives and sealants D, polymer... Fig. 7. U.S. production and consumption of styrene block copolymers (104). A, Total production B, consumption C, adhesives and sealants D, polymer...
Global consumption of thermoplastic mbbers of all types is estimated at about 600,000 t/yr (51). Of this, 42% was estimated to be consumed in the United States, 39% in Western Europe, and 19% in Japan. At present, the woddwide market is estimated to be divided as follows styrenic block copolymers, 48% hard polymer/elastomer combinations, 26% thermoplastic polyurethanes, 12% thermoplastic polyesters, 4% and others, 9%. The three largest end uses were transportation, 23% footwear, 18% and adhesives, coatings, etc, 16%. The ranges of the hardness values, prices, and specific gravities of commercially available materials are given in Table 4. [Pg.15]

The tonnage of plasticisers consumed each year exceeds the annual tonnage consumption of most plastics materials. Only PVC, the polyolefins, the styrene polymers, the aminoplastics and, possibly, the phenolics are used in large quantity. [Pg.330]

In addition to polystyrene and high-impact polystyrene there are other important styrene-based plastics. Most important of these is ABS, with a global capacity of about 5 X 10 t.p.a. and production of about 3 X 10 t.p.a. The styrenic PPO materials reviewed in Chapter 21 have capaeity and production figures about one-tenth those for ABS. Data for the more specialised styrene-acrylonitrile copolymers are difficult to obtain but consumption estimates for Western Europe in the early 1990s were a little over 60000 t.p.a. [Pg.426]

Table 16.12 Production and consumption breakdown for main types of styrene-based plasties in the late 1990s... Table 16.12 Production and consumption breakdown for main types of styrene-based plasties in the late 1990s...
About 8,000 metric tons of peroxides were consumed in 1972. This consumption was strongly stimulated by the rapid growth in reinforced plastics (Ref 23). The largest volume product is benzoyl peroxide which is used in polystyrene and polyester markets for such items as toys, automobiles, furniture, marine, transportation and mil requirements. Also, methyl ethyl ketone peroxide is used in large volumes to cure (as a catalyst) styrene-unsatur-ated polyester adhesive resins used in mil ammo adhesive applications, as well as in glass fiber reinforced plastic products such as boats, shower stalls, tub components, automobile bodies, sports equipment, etc. The monoperesters are growing slowly because of some substitution of the peroxydicarbonates and azo compds (Refs 8,9 23)... [Pg.676]

The styrene conversion versus reaction time results for runs in the laminar flow regime are plotted in Figure 8. Both the rate of polymerization and the styrene conversion increase with increasing flow rate as noted previously (7). The conversion profile for the batch experimental run (B-3) is presented as a dashed line for comparison. It can be seen that the polymerization rates for runs with (Nj e e 2850 are greater than the corresponding batch polymerization with a conversion plateau being reached after about thirty minutes of reaction. This behavior is similar to the results obtained in a closed loop tubular reactor (7J) and is probably due to an excessively rapid consumption of initiator in a... [Pg.123]


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See also in sourсe #XX -- [ Pg.14 ]




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