Poly , PEMA

Surprisingly, the addition of TBA to a solution of living poly-PEMA also leads to the quantitative formation of a block copolymer as Is shown by GPC analysis (Figure 4). This proves that the rate constant of the Initiation for the TBA polymerization by the PEMA azlrldlnlum Ion Is of the same order of magnitude as the homopropagation constant for TBA or k2i 1 11 ... 

Figure 3. GPC analysis of poly-TBA-poly PEMA block-copolymer (A) and of the poly-TBA used as the macromolecular initiator(B).

Poly(ethyl methacrylate) (PEMA) yields truly compatible blends with poly(vinyl acetate) up to 20% PEMA concentration (133). Synergistic improvement in material properties was observed. Poly(ethylene oxide) forms compatible homogeneous blends with poly(vinyl acetate) (134). The T of the blends and the crystaUizabiUty of the PEO depend on the composition. The miscibility window of poly(vinyl acetate) and its copolymers with alkyl acrylates can be broadened through the incorporation of acryUc acid as a third component (135). A description of compatible and incompatible blends of poly(vinyl acetate) and other copolymers has been compiled (136). Blends of poly(vinyl acetate) copolymers with urethanes can provide improved heat resistance to the product providing reduced creep rates in adhesives used for vinyl laminating (137). 

IPS Impact polystyrene PEMA Poly(ethyl methacrylate)... 

This analysis leads to the conclusion that equation 1 is obeyed well by certain anthracene/polymer combinations, but there are significant deviations for others. DMA/PEMA (poly(ethyl methacrylate)) and DPA/PBMA (poly(butyl methacrylate)) fit equation 1 exactly, while DPA/PEMA (both with and without sensitizer) and DPA/PDPS (poly(diphenylsiloxane)) deviate the actual reaction proceeds more slowly with dose than predicted, and the deviation increases as the dose increases. 

Figure 10 Separation of a homopolymer mixture of poly (ethyl methacrylate) (PEMA), polystyrene (PSTY) and poly (lauryl methacrylate) (PLMA) by Orthogonal Chromatography at different % n-heptane concentrations in SBC 2.

As noted in the introduction, the first successful studies of PCS near the glass transition in polymers employed thermally polymerized styrene. The monomer was dried over calcium hydride and vacuum distilled directly into the scattering cell. This procedure was also successfully employed to prepare poly(methyl methacrylate)(PMMA)28) and poly-(ethyl methacrylate)(PEMA)29). Although our own samples were all prepared without... 

The effect of the side chain bulkiness has been further studied on a series of chloro derivatives of poly(ethyl methacrylate)(PEMA). Though poly(2-chloroethyl methacrylate) exhibits69 a pronounced peak at Ty = 117 K, poly(2,2,2-trichloroethyl methacrylate), poly(2,2,2-trichloro-l-methoxyethyl methacrylate), and poly(2,2,2-trichloro-l-ethoxyethyl methacrylate) do not show (Fig. 6) any low-temperature loss maximum above the liquid nitrogen temperature157. However, these three polymers probably display a relaxation process below 77 K as indicated by the decrease in the loss modulus with rising temperature up to 100 K. Their relaxation behavior seems to be similar to that of PEMA rather than of poly(2-chloroethyl methacrylate) which is difficult to explain. 

The homopolymers poly(methyl methacrylate) and poly-(ethyl methacrylate) are compatible with poly(vinylidene fluoride) when blended in the melt. True molecular com-patibility is indicated by their transparency and a single, intermediate glass transition temperature for the blends. The Tg results indicate plasticization of the glassy methacrylate polymers by amorphous poly(vinylidene fluoride). The Tg of PVdF is consistent with the variation of Tg with composition in both the PMMA-PVdF and PEMA-PVdF blends when Tg is plotted vs. volume fraction of each component. PEMA/PVdF blends are stable, amorphous systems up to at least 1 PVdF/I PEMA on a weight basis. PMMA/ blends are subject to crystallization of the PVdF component with more than 0.5 PVdF/1 PMMA by weight. This is an unexpected result. 

Tn the early 1960s it was discovered in our laboratory (20) that poly-- (methyl methacrylate) (PMMA) and poly(vinylidene fluoride) (PVdF) were compatible when blended in the melt. Similarly, compatibility was found for poly (ethyl methacrylate) (PEMA) with PVdF. Blends of the fluorinated polymer with higher alkyl methacrylate polymers, however, were nonhomogeneous. 

Physical Properties of PMMA—PVdF and PEMA—PVdF Poly blends. 

Fig. 1.17 Comparison of theory and experiment for preferential adsorption coefficient, X, of poly(alkyl methacrylate)s in 1,4-dioxane-methanol. (pso = methanol volume fraction). Points Experimental results from ref. [6], (o) PMMA (alkyl = Me) (A) PEMA (Et) ( ) PiBM (iBu). Association equilibria theory. (2-A) Calculated with the parameter values shown in Table I and numbered as 4-6, Curves (a) PMMA (b) PEMA, (c) PiBMA. (2-B) Calculated with the parameter values shown in Table I and numbered as 10-12. Curves (a) PMMA (b) PEMMA (c) PiBMa. (From ref. [120])...

PE PEMA PEO PIP PMAA PMMA PMPS poly(ethylene) poly(ethyl methacrylate) poly(ethylene oxide) poly(isoprene) poly(methacrylic acid) poly(methylmethacrylate) poly(methylphenylsiloxane)... 

An interesting result with respect to applications obtained with the IPN hydrogels is that these are two- phase systems (two glass transition temperatures), with the hydrophilic domains behaving essentially like the pure hydrophilic component.6,7,9 Thus, the two basic functions of these IPN hydrogels with respect to applications, namely hydrophilicity and mechanical stability, are separately taken over by the two IPN components, the hydrophilic and hydrophobic domains, respectively. Figure 1 shows TSDC and DMA results for the water content dependence of the a relaxation (dynamic glass transition) of PHEA in sequential IPNS prepared from PHEA and poly(ethyl methacrylate) (PEMA) as the hydrophobic component.9 In these IPNs a porous PEMA network was prepared first, and PHEA was then polymerized in the pores. In addition to the... 

PEMA PEO PIEO POX) P(b-EO b-POX) PIER HBA) polylethyl methacrylate) polylethylene oxide) polylethylene oxide-co-propylene oxide) polylblock-ethylene oxide-co-block-propylene oxide) poly(ethyleneterephthalate-co-p-hydroxibenzoic acid)... 

The next three polymers in this series are aU ethyl acrylates, meaning that while the backbone (a) substituent is different in all three structures, the ester side-chain group (P) is the same for aU of them ( CH2CH3). Polymer 3 is poly(ethyl methacrylate) (PEMA), and 4 is poly(ethyl cyanoacrylate) (PECA), which may be recognizable as a primary component of the so-called superglues. Polymer 5 is poly(ethyl acrylate) (PEA), with H on the backbone a-position. Erom structure 3 to 4 to 5, the a-substituent becomes simpler in structure and this will be reflected in the observed TREPR spectra below in terms of the number of observed transitions, and in some cases the linewidths as well. 

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