Poly methyl methacrylate Polymer PMMA

Poly(methacrylates) are polymers of the esters of methacrylic acids. The most commonly used among them is poly(methyl methacrylate) (PMMA). Poly(methyl methacrylate) or poly(methyl 2-methylpropenoate) is the polymer of methyl methacrylate, with chemical formula It is a clear, colorless polymer available on the market 

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Iso tactic poly(methyl methacrylate) (it-PMMA) can form a stereocomplex with st-PMMA. Recent X-ray studies 179) of this material indicate that the two polymer chains probably interact to form a double helical structure. The it-PMMA chain forms the inner helix and is surrounded by the st-PMMA helical chain which winds around it. If subsequent work confirms this model, this material would constitute a most unusual inclusion compound involving only one monomeric substance. 

Hard contact lenses are composed of a polymer that repels water because the constituent repeating units (the monomers that link together to form the polymer) are nonpolar, hydrophobic segments. The first hard contact lens was constructed in 1948 from the monomer known as methyl methacrylate (MMA), yielding the polymer poly(methyl methacrylate) or PMMA. This material offers durability, optical transparency, and acceptable wettability for optimal comfort. Today the rigid lens material of hard contact lenses is often constructed by combining MMA with one or more additional hydrophobic monomers to provide better gas permeability. 

Union of Pure and Applied Chemists (IUPAC) has developed systematic nomenclature rules for polymers. As is the case with many small-molecule organic compounds, the IUPAC names are often complex and cumbersome. Therefore, polymer scientists often use common or abbreviated names, sometimes even product names. Poly[l- methoxycarbonyl)-l-methylethylene] (IUPAC) is almost always referred to as poly(methyl methacrylate), or PMMA, or even Lucite. IUPAC discourages the use of trademarked names, however unless it is importanfto refer to a specific commercial product. The IUPAC Macromolecular Nomenclature Commission recognizes a number of trivial names for common polymers (Metanomski 1999). 

In our preliminary report (2), we have chosen poly (methyl methacrylate) or PMMA as a host polymer and methyl acrylate as the guest monomer. They were both crosslinked by a divinyl acrylic monomer. However, because of the similarity in the constitutions of these two components, it was not possible to establish the gradient profile through chemical analysis. In this work, we have selected a halogenated acrylic monomer as the second component to be diffused into PMMA. By analyzing the halogen content, it was possible to determine the profiles of the gradient polymers. Stress-strain measurements of the samples were then carried out on these unique materials. 

This paper reviews the application of IGC in determining interaction parameters for three polymer blend systems polystyrene-poly(n-butyl methacrylate) (PS-PnBMA), polystyrene-poly(2,6-dimethyl-1,4-phenylene oxide) (PS-PPO), and poly(vinylidene fluoride)-poly(methyl methacrylate) (PVF2-PMMA)... 

Li, Y., Zhao, B., Xie, S., and Zhang, S. 2003. Synthesis and properties of poly(methyl methacrylate)/ montmorillonite (PMMA/MMT) nanocomposites. Polymer International 52 892-898. 

Commercial acrylic resins comprise a broad array of polymers and copolymers derived from esters of acrylic acid and methacrylic acid. They range from the homopolymer of methyl methacrylate to a variety of copolymers including both the thermoplastic and thermoset type and ranging from hard and stiff types to soft and elastomeric types. The most common of the thermoplastic acrylic resins are the poly(methyl methacrylate) homopolymer (PMMA) and the copolymers containing predominantly methyl methacrylate but with small amounts of methyl or ethyl acrylate, acrylonitrile, or styrene comonomers added for improved toughness. 

Fig.18 Height (AFM) and friction (LFM) images of a spin-cast polystyrene/poly(methyl methacrylate) polymer blend [PS/PMMA (1 10 w/w)], obtained with (a) gold-coated and (b) SiO tips under perfluorodecalin. (Reprinted with permission from [125]. Copyright 1998 American Chemical Society)...

The method of differential radiation induced contrast depends on enhancement of contrast in multicomponent polymers where the components have different electron beam-polymer interactions [173]. Contrast has been observed in sections of styrene-acrylonitrile/poly(methyl methacrylate) (SAN/PMMA) polymers where the PMMA exhibits a high rate of mass loss compared to SAN, creating contrast between the phases. It is well known that electron irradiation results in chain scission and crosslinking, loss of mass and crystallinity [75]. Polystyrene, polyacrylonitrile and SAN crosslink and thus are stable in the electron beam whereas polymers exhibiting chain scission, PMMA and poly(vinyl methyl ether), degrade in the beam. It is suggested that experiments be conducted on the homopolymers to determine the expected irradiation damage mechanism in the multi-component system [173]. 

It is important to understand that solubility does not indicate the absence of interactions between the polymer and the stationary phase and insolubility of a polymer does not provide information on interaction effects with the stationary phase. Solubility refers to the binary system of polymer and solvent, while eluent strength refers to the interplay of the interactions among stationary phase, mobile phase, and polymer. As an example, chloroform is a good solvent for poly(methyl methacrylate). However, PMMA is strongly retained on a polar silica column when using chloroform as the eluent, since there is a pronounced interaction of the polar repeating units with the stationary phase. In contrast, on styrene-divinylbenzene-based columns, PMMA clearly elutes in the SEC mode before the injected solvent, indicating that no adsorption of the PMMA onto the stationary phase occurs under these conditions. 

Using FRES and others techniques, Wang and Composto investigated wetting and phase separation in polymer blend films composed of deuterated poly(methyl methacrylate) (d-PMMA) and poly(styrene-raw-acrylonitrile) (h-SAN) at the critical concentration [176-180]. This blend is characterized by a lower critical solution temperature (LCST) behavior with Tlcst 160 °C and 0d-PMMA 0.5 [180]. In this... 

By applying microwave conditions, it was possible to obtain bromo-double-terminated polystyrene (Br-PS-Br) and poly(methyl methacrylate) (Br-PMMA-Br) with predesigned molecular weight and narrow polydispersity prepared by ATRP. The polymers were reacted with excess amounts of fullerene Cgo... 

For the polymerization of tert-butyl acrylate, the monomer consumption followed the first-order kinetics, while that of MMA could be described with a kinetics model that includes the persistent radical effect. The control over the reaction could be preserved for monomer conversions of up to 90%, and poly(methyl methacrylate) s (PMMAs) with narrow molecular weight distributions (PDI below 1.3) were obtained. Conventional experiments with an oil bath showed a limited reproducibility and furthermore failed to yield polymers with similar narrow molecular weight distributions (for high conversions). This observation was refereed to the superiority of the uniform, noncontact, and internal heating mode of micro-wave irradiation. 

Kusuyama, H., Yakase, M., Higashihata, Y, Tseng, H. T, Chatani, Y, Tadokoro, H. Structural change of syndiotactic poly (methyl methacrylate) (st-PMMA) on drawing, absorption and desorption of solvents. Polymer, 23,1256-1258 (1982). 

Polar monomers such as 2-vinylpyridine and methyl methacrylate are normally polymerized in polar solvents such as tetrahydrofuran and at low temperature (-78 °C). In addition, additives such as LiCl are often added to help lower the rates of termination reactions to levels insignificant in the time frame of the reaction. Block copolymers made with nonpolar and polar monomers start with the nonpolar monomer because of its greater reactivity. These active centers are then typically capped with 1,1-diphenylethylene to lower then-reactivity before the addition of the polar monomer. This helps eliminate side reactions resulting from addition of the active center to electrophilic sites in the polar monomers. The two polar polymers, polystyrene-2-vinylpyridine (PS-P2VP) and polystyrene-poly methyl methacrylate (PS-PMMA) have been extensively studied in thin films. 

Very few papers have been published on the preparation of polymer blend nanocomposite from organoclays and poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) blend by the solution blending method." In this section, we discuss how the blending sequence affects the microstructure of the ternary hybrid nanocomposites and especially the dispersion states of the organoclays in the polymer matrix. 

Figure 2 illustrates the molecular weight dependence of (S )/M for isotactic poly(methyl methacrylate) (i-PMMA) in acetonitrile, a-PMMA in acetonitrile, and atactic polystyrene (PS) in cyclohexane, all at the theta point. The curves represent the theoretical values calculated from eqn [12] with the HW chain parameters listed in Table 1. Their close fits to the data points for the respective polymers demonstrate the excellent applicability of the HW model to the flexible polymers. In particular, the peak of (S )/M around M = 1.2 x 10 for a-PMMA shows behavior typical of a chain with locally helical conformation. On the other hand, the monotonic rise of (S )/M with increasing M for PS indicates weak helical nature of the polymer. In this chapter, we often use the KP model for describing solution behavior of PS. 

Mixtures of polymers at surfaces provide the interesting possibility of exploring polymer miscibility in two dimensions. Baglioni and co-workers [17] have shown that polymers having the same orientation at the interface are compatible while those having different orientations are not. Some polymers have their hydrophobic portions parallel to the surface, while others have a perpendicular disposition. The surface orientation effect is also present in mixtures of poly(methyl methacrylate), PMMA, and fatty acids. 

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