Poly ethane

CH2)2-0-C hC-0 0 — 0 poly(phenylene oxide) poly(ethane-1,2-diyl terephthalate) poly(oxy-1,4-phenylene) poly(oxy ethane-1,2-diyloxy-terephthaloyl)... 

Poly(ethane-l,2-diyl/l-hydroxyethane-l,2-diyl) grafted with polystyrene [poly(l-phenylethane-l,2-diyl)] at hydroxymethylene units ... 

E3 poly[(ethane-l,2-diol)-a/C(terephthalic acid isophthalic acid)]... 

Recently it was disclosed in a Japanese patent that the copolymers of hexanal with propanal, butanal and isobutanal could be used as self-developing X-ray resists of 200 — 400 mJ/cm2 sensitivity (32). Our poly(ethanal-co-butanal) showed the sensitivity of 30 mJ/cm2 on the exposure to X-ray radiation without requiring a wet development process (Table VIII). Other copolymers also functioned as a positive self developing X-ray resist. 

Table IX. Electron-beam Exposure Characteristics3 of Poly(ethanal-co-butanal)s of Various Molecular Weights Prepared in Toluene at —78°C with Et2AlNPh2...

We noted in Chapter 10 that some scientific discoveries take place by accident , for example the discovery of poly(ethane) and PTFE in the polymer industry, and of cyanoacrylate superglues. The skill of exploiting an unexpected, but possibly significant, outcome must credited to the scientists involved. 

H. Tang and C. Beatty, Blends of Poly(ethane-co-octene) Elastomers , SPE-ANTEC Tech. Papersp. 3870-3874, (2000)... 

About 35% of total U.S. LPG consumption is as chemical feedstock for petrochemicals and polymer iatermediates. The manufacture of polyethylene, polypropylene, and poly(vinyl chloride) requires huge volumes of ethylene (qv) and propylene which, ia the United States, are produced by thermal cracking/dehydrogenation of propane, butane, and ethane (see Olefin polymers Vinyl polymers). 

The small molecules used as the basic building blocks for these large molecules are known as monomers. For example the commercially important material poly(vinyl chloride) is made from the monomer vinyl chloride. The repeat unit in the polymer usually corresponds to the monomer from which the polymer was made. There are exceptions to this, though. Poly(vinyl alcohol) is formally considered to be made up of vinyl alcohol (CH2CHOH) repeat units but there is, in fact, no such monomer as vinyl alcohol. The appropriate molecular unit exists in the alternative tautomeric form, ethanal CH3CHO. To make this polymer, it is necessary first to prepare poly(vinyl ethanoate) from the monomer vinyl ethanoate, and then to hydrolyse the product to yield the polymeric alcohol. 

Fig. 17. Chemical structures of anionic amphiphile sodium l,2-bis((tetradecyloxy)carbonyl) ethane-1-sulfonate (2Ci4SNa) and poly(ethylenimine)(PEI).

Figure 17 shows the chemical structures of anionic amphiphile sodium-1,2-bis (tetradecylcarbonyl)ethane-l-sulfonate (2Cj4SNa)[34] and poly(ethyleneimine)(PEI). A benzene/ethanol (9 1)(WV) solution of anionic amphiphile was spread on the pure water surface or the PEI-water solution (lxlO5 unit M in monomer unit, pH=3.2) surface at a subphase temperature, Tsp of 293 K. At this pH, ca. 70 % of nitrogen atom in PEI molecule was protonated[35]. Surface pressure-area(ji-A) isotherms were measured with a microprocessor controlled film balance system. 

Free electron pairs are a good source for an electron which is to be ejected and therefore, the IE of ethanol and dimethylether is lower than that of ethane. It has been shown that the IE of a poly-substituted alkane is almost the same as the IE of the structurally identical mono-substituted alkane which has the lowest value. [27] The other substituent, provided it is separated by at least two carbon atoms, exerts a very small effect upon the IE, e.g., the IE of dimethylsulfide, CH3SCH3, 8.7 eV, is almost the same as that of methionine, CH3SCH2CH2CH(NH2)COOH. Introduction of an oxygen decreases the IE less than nitrogen, sulfur or even selenium do, since these elements have lower electronegativities and thus, are even better sources of an electron. 

Fig. 15 Dry thickness, /z, (open symbols) and wet thickness, ff, (closed symbols) of poly(acryl amide) (PAAm) and the l-trichlorosilyl-2-(m-p-chloromethylphenyl) ethane (CMPE) concentration (solid line) as a function of the position on the substrate for samples prepared on substrates containing the initiator gradients made of CMPEiPO mixtures (w/w) a 1 1 ( , ), b 1 2 (o, ), and c 1 5 (A, A). (Reproduced with permission from [76])...

Fig. 1. Side view (above) and end view (below) of the macromolecule of isotactic poly[l-(l-naphthyl)ethane-l,2-diyl] in the crystalline state. The helix symbol is s(2 4/1). The chain axis is shown by the dashed line, and c is the chain identity period. Hydrogen atoms are omitted. [From P. Corradini and P. Ganis. Nuovo Cimento, Suppl. 15, 96 (I960)].

CHCH2-) - OH poly(vinyl alcohol) poly( 1 -hydroxy ethane-1,2-diyl)... 

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