Transmission graft copolymer

Figure 2. Morphology of various cross-polybutadiene-in/er-cross-polystyrene sequential IPNs and graft copolymers via transmission electron microscopy. The double bonds in the polybutadiene phase are stained dark with osmium tetroxide. (Reproduced from ref. 15. Copyright 1976 American Chemical Society.)...

Fig. 3b. Graft copolymer microstructure (transmission electron micrograph, ultramicrotome section) after processing to a milled sheet...

Figure 3.4. Illustration of phase inversion during polymerization (Molau, 1965). Electron micrographs (transmission) of thin sections of a graft copolymer of p-t-butylstyrene with polystyrene (90/10). (a) Polymerized to 5.3 % conversion before the inversion point. The poly(p-t-butylstyrene) phase is white, and the polystyrene phase is black, (b) Polymerized to 7.8% conversion phase inversion is just beginning to occur, (c) The same system polymerized to 13.3% conversion after the phase inversion point.

Figure 2.3. Six morphologies of graft copolymers, IPNs, and semi-IPNs of SBR/polystyrene. The SBR component is stained dark by osmium tetroxide for transmission electron microscopy. The type of morphology evolved depends on the synthetic detail. ...

Figure 4.15 Phase morphology of graft copolymers and IPNs of SBR rubber and polystyrene by transmission eiectron microscopy. Upper two figures, graft oopoiymers middie two, semi-iPNs bottom two, fuii iPNs. Diene portion stained dark with OSO4 (50),...

The graft copolymerizations were carried out with various grafting efficiencies (34.6-95.1%) in dichloromethane (DCM), chloroform, and DMF at room temperature for 21 hrs. up to 210 hrs. The microstructure of the graft copolymers was studied using transmission electron microscopy. A... 

Portions of these spectra, that refer to the IR-ATR and to IR-transmission measurements carried out on PsBPP-g-PMMA grafted copolymers, are reported in Figures 7 and 8, respectively. The absorbance measured by transmission spectroscopy is remarkable higher than that obtained by ATR superficial measurements. This seems to indicate that the grafting process of the organic polymer onto the polyphosphazene support takes place predominantly in the bulk of the polyphosphazene matrix and that only a minor part of PNNDMAA is grafted onto the surface of the POP films. This is in agreement with the above mentioned abilities of MMAM to swell the polyphosphazene substrates. 

One such system involved grafting 70 parts of methyl methacrylate on to 30 parts of an 81-19 2-ethylhexyl acrylate-styrene copolymer. Such a grafted material was claimed to have very good weathering properties as well as exhibiting high optical transmission. 

The importance of the graft handle on a 62/38 butadiene-methyl methacrylate rubber can be illustrated by its effect on the optical properties of the polyblend. From Table II it can be seen that the reduction in percent haze is dramatic for an increase of methyl methacrylate graft from 0 to 27% by weight, while there is no apparent change in the light transmission. The blend resin in this polyblend system was an 88-12 methyl methacrylate-styrene copolymer, and the total resin to backbone rubber ratio was kept at 2.5-1.0. The measured refractive indices are included for each component (the graft rubber and the blend resin). The difference in refractive index amounts to no more than 0.004 unit for any of the components. 

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