Poly ethyl methacrylate , PEMA

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). 

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. 

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. 

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... 

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. 

Poly(methyl methacrylate) (PMMA) and poly(ethyl methacrylate) (PEMA) cross-linked with ethylene glycol dimethacrylate (EGDM)... 

Cosolvents can enhance solubility of compounds in CO2, a topic beyond the scope of this chapter. It is useful, however, to point out some details on cosolvents in CO2. McHugh et al. demonstrate that a cosolvent can provide the specific interactions that are necessary to solubilize a compound in CO2 (70,71). For instance, butyl acrylate (BA) and ethyl hexyl acrylate (EHA) decrease the cloud point pressure of acrylate polymers owing to the specific polar interactions between the cosolvent with the acrylate backbone of the polymer (70). Addition of ethyl methacrylate (EMA) and butyl methacrylate (BMA) reduces the pressure needed to solubilize poly(ethyl methacrylate) (PEMA) and poly(butyl methacrylate) (PBMA) in CO2 (71). 

A scheme of the experimental setup is shown in Fig. 83, where a laser beam (355 nm, 3 ns) is directed from the rear of the target film onto the triazene polymer film (doped with pyrene) as shown in Fig. 82. The laser fluence was estimated by averaging the total energy of the incident beam over the irradiated area. The target films [poly(butyl methacrylate), PBMA, Tg=293 K and poly(ethyl methacrylate), PEMA, Tg=338 K] were characterized with a fluorescence microscope and a conventional spectrofluo-rometer. 

Fig. 84 Comparison of fluorescence and optical microscopic images of poly(butyl methacrylate) PBMA (a) and (c), and poly(ethyl methacrylate) PEMA (b) and (d) target polymer sin-face following 355-nm laser-induced molecular transfer of pyrene contained in triazene polymer. Irradiation dose 5 pulses, 200 mj cm-2. The bar denotes 100 jltm in each case. REPRINTED WITH PERMISSION OF [Ref. 360], COPYRIGHT (1998) Elsevier Science...

Poly[l-(ethoxycarbonyl)-l-methylethylene] (atactic) Poly(ethyl methacrylate) [PEMA] Poly[l-(ethoxycarbonyl)-l-methylethylene] (isotactic) Poly[l-(ethoxycarbonyl)-l-methylethylene)] (syndiotactic) Poly[l-(hexyloxycarbonyl)-l-methylethylene] Poly[l-(isobutoxycarbonyl)-l-methylethylene] Poly[l-(isopropoxycarbonyl)-l-methylethylene]... 

FIGURE 13.23 Plot of against frequency for the P-relaxation in poly(methyl methacrylate) PMMA (0,0) poly(ethyl methacrylate) PEMA ([ ], ) poly(n-propyl meth-... 

Another example from polymer blends can be taken from the dynamics of the faster poly(ethyl methacrylate) (PEMA, Tg = lA C) component in blends with poly(4-vinylphenol) (PVPh, Tg = 171 C) (Zhang et al 2002). Neat PEMA has a resolved JG relaxation, which is continued to be observed in the blend and practically unchanged with blending. Since Tg of the PEMA component in the blend is shifted to higher temperature by the slower poly(4-vinylphenol) component, therefore ogXaf Tgf) - ogxpf Tgf)) of the PEMA component increase at constant Xa(Tg). 

In this study, the specific polymers of interest are poly(2,2,2-tri iuoroethyl methacrylate), PTFEMA, poly(2,2,2-trifluoroethyl acrylate), PTFEA, and poly(hexa-fluoroisopropyl aaylate), PHFiPA, with the respective non-fiuorinated counterparts, poly(ethyl methacrylate), PEMA, poly(ethyl acrylate), PEA, and poly(isopropyl acrylate), PiPA. 

Figure 3.18 shows the dCp/dT signal versus temperature for different PMA/PVAc blend compositions. The dCp/dT signal showed a high degree of symmetry, which implies that the miscibility level is high. Compare this with the behaviour of PVC/poly(ethyl methacrylate) (PEMA) blends. 

Static SIMS is capable of obtaining very reproducible fingerprint spectra from bulk polymer surfaces. For example, static SIMS can easily distinguish between poly(methyl methacrylate) (PMMA) and the structurally similar poly(ethyl methacrylate) (PEMA) (Figure 9) based upon the unique negative ion fragmentation pattern obtained from each polymer. PEMA has a monomer repeat unit mass of 114 amu ... 

Also included in Table 13.1 are data for several poly-(alkyl methacrylates) including poly(methyl methacrylate) (PMMA) (5), poly(ethyl methacrylate) (PEMA) (6), poly-(2-hydroxyethyl methacrylate) (PHEMA) (7), poly(n-propyl methacrylate) (PnPMA) (8), poly( -butyl methacrylate) (PnBMA) (9), and poly (isobutyl methacrylate) (PiBMA) (10). 

Poly(ethyl methacrylate) PEMA Poly(n-butyl methacrylate) 373 11.18 103.5 335 [86] 37,s of the softening dispersion from dynamic shear compliance J (co) from 352.7 to 428°K. 

Poly(Ethyl Methacrylate) (PEMA) as Polymer Matrix. 52... 

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