PolyMMA

Table 4. Comparison of the stereoregularity of polyMAOA, polyMAOU and polyMAOThe with that of polyMMA derived from them...

Contact Angle of Water Droplet at 20°C for Various Siloxane Polymers-PolyMMA Blend Films. 

Figure 3. ESCA Relative Intensity of polyMMA Blend Films Containing Various Amounts of Siloxane Graft Copolymer GM411.

The MALDI-TOF-MS analysis of the polyMMA, obtained in linear mode shows only one series of peaks, whose interval was regular, ca. 100, the molar mass of MMA unit. It indicates the absence of irreversible chain termination processes via recombination or disproportionation. According the proposed mechanism of polymerization the absolute masses of the peaks should be equal... 

Figure 3. The MALDl-TOF mass spectrum of the obtained polyMMA...

Figure 5. (A) Initiation efficiency of different ATRP initiators during the homopolymerization ofMMA, and (B) comparison of experimental gel points duringATRcP ofMMA andEGDMA by using different initiators with various ratios of X = [EGDMA]/[Initiator] experimental conditions [MMA](/[Initiator](/[CuBr](/[CuBr2](/[bpy]o = 50/1/0.4/0.1/1 for ATRP, and [MMA] (/[EGDMA](/[Initiator] o/[CuBr](/[CuBr2](/[bpy]o = 50/X/I/0.4/0.I/I for A TRcP, [MMA]o = 5.0 M in acetone at 50 °C linear polyMMA standards for...

Generally, the conditions leading to a CRP system were found to yield a well-defined polymer shell. In some examples, the latter was a classical hydrophobic polymer such as polyMMA [158,160], polyMA [158], polystyrene [163], poly(tert-butyl acrylate) [163], or polyBMA [163]. In one example, the grafted polymer was polyDMAEMA, which showed pH- and temperature-responsive behavior when the particles were further transferred to water [159]. The polyDMAEMA domains were used as nanoreactors to generate gold nanoparticles at the particle surface, the catalytic activity of which was effective in the reduction of 4-nitrophenol by NaBILj... 

It has been indicated already (see section 3.1.1) that, under some circumstances, NMR studies of end-groups can lead to values of number-average molecular weights of polymers. It has been found for polyMMA prepared using [jS, jS- C]AIBN[l] and for polySTY made with [a-AIBN[9] that satisfactory results can be obtained. The conditions for recording the spectra must be carefully selected and it is necessary to have information on the average number of initiator fragments per polymer molecule, i.e. on the relative importance of combination and disproportionation in the termination steps of the polymerizations and also on the frequencies of transfer reactions. 

Generally there is fair agreement between selectivity in the reactions of a polymer radical with monomers and that in the corresponding reactions of the appropriate model radical. This feature can be well illustrated by considering the case of STY and MMA with the radicals Me CHPH and Me2C(COOMe) as expected from studies of copolymerizations, MMA is about twice as reactive as STY towards the radical regarded as a model for the poly STY radical whereas it is about half as reactive towards the radical representing a polyMMA radical [5]. 

C]BPO has been used in extensive studies of the participation in radical polymerizations of unsaturated substances not usually regarded as comonomers. Much of the work has involved stilbene and similar substances that show unexpectedly high reactivities towards the benzoyloxy radical. These additives become incorporated in polyMMA, for example, mainly at sites very close to the end-groups the resulting structures may be useful in subsequent attempts to modify the polymers. 

Figure 3.4 Parts of the 100 MHz NMR spectra of samples of polyMMA made using [ C]BPO,...

An application of NMR for study of end-groups in polymers produced by anionic polymerization involved use of the spin-echo technique [23]. It was applied for detection of tert-hutyl end-groups in polyMMA made using unenriched di-t rt-butyl magnesium as initiator. 

Fig. 6. ESR spectrum of radical trapped in polyMMA in polymerization of MMA at room temperature ...

Fig. 7a-c. Possible reconstraction of 9-line spectrum (a) observed ESR spectrum of y-irradiated polyMMA (b) suggested reconstraction (c) projections (0, 9 ) of the C—H bonds of P-methylene on the plane perpendicular to the C,—C, bond... 

Fig. 16a and b. Temperature dependence of intensity distribution of polyMMA radical (a) in anisole at —120 °C (b) in benzonitrile at indicated temperatures... 

The spectrum (b) in Fig. 49 is for the growing radical of polyMMA. Bresler attributed it to the overlap of 5 lines spaced at 23 G with the intensity distribution 1 4 6 4 I and 4 lines with the intensity distribution 1 3 3 1. Their simultaneous appearance was ascribed to two possible monomer additions. 

---