Polyvinyl methyl ether

Triclosan is retained in dental plaque for at least 8 hours, which in addition to its broad antibacterial property could make it suitable for use as an antiplaque agent in oral care preparations. However, the compound is rapidly released from oral tissues, resulting in relatively poor antiplaque properties as assessed in clinical studies of plaque formation. This observation is further corroborated by a poor correlation between minimal inhibitory concentration values generated in vitro and clinical plaque inhibitory properties of triclosan. Improvement of substantivity was accomplished by incorporation of triclosan in a polyvinyl methyl ether maleic acid copolymer (PVM/MA, Gantrez). With the combination of PVM/MA copolymer and triclosan, the substantivity of the triclosan was increased to 12 hours in the oral cavity. 

Polyvinyl methyl ether has the following repeating unit ... 

Polyvinyl methyl ether and polymers of acrylic and methacrylic add are also water-soluble. Because of salt formation in the polymers, the acrylic and methacrylic acid polymers, as well as CMC, are more soluble in alkaline solutions than they are in water. 

C NOE spectroscopy under MAS was used for probing polymer miscibility in polymer blends, polystyrene/polyvinyl methyl ether (PS/PVME) [42], This study takes advantage of the fact that crosspeaks appear only between spins that are neighbours of each other,... 

We briefly describe here the results obtained from studies of copper, nickel and chromium overlayers deposited on polystyrene, polyvinyl alcohol, polyvinyl methyl ether, polyethylene oxide, polyvinyl acetate and polymethyl methacrylate. Using X-ray photoemission spectroscopy we measured significant variations in the core binding energies and lineshapes as we varied both the metal and the substrate atoms. These changes can be related to both differences between the intrinsic properties of the metal atoms as well as to differences in the interactions with the substrates. In the following sections we describe the details of... 

The interfaces formed by evaporating copper, nickel and chromium layers on polystyrene, polyvinyl alcohol, polyethylene oxide, polyvinyl methyl ether, polyvinyl acetate and polymethyl methacrylate have been studied with X-ray photoemission spectroscopy (XPS). At submonolayer coverages of the metals, the peak positions and widths of the metallic electron core levels vary significantly from one polymer substrate to another. Most of... 

The absolute values of Da for the phase separation and phase dissolution are plotted against e in log-log scale together in Figure 13. In the present case, the value of v turns out to be unity for the phase separation as well as for the phase dissolution, thereby confirming the prediction of linearized theory. A similar observation was also made by Snyder and coworkers (2Q) for the polystyrene (PS) polyvinyl methyl ether (PVME) blends. It is concluded that the diffusion rate is the same for the 60,000 and 100,000 molecular weight HPC specimens, if the diffusivities are referenced to the spinodal temperature. 

Neutral or negatively charged polymeric resins are commonly employed to provide styling benefits in products such as mousses, gels, hairsprays, and setting lotions. Typical examples in use today are the copolymer of vinyl acetate and cro-tonic acid, the copolymer of polyvinyl pyrrolidone and vinyl acetate (PVP/VA), the ethyl ester of the copolymer of polyvinyl methyl ether and maleic anhydride (PVM/MA), and the copolymer of octylacrylamide/acrylates/butylaminoethyl methacrylate (Amphomer). 

For such an experiment to work, we have to be able to distinguish the different domains during the evolution and the detection period of the two-dimensional experiment. Since proton spectral resolution in typical solids is very poor, we have to use homonuclear dipolar-decoupling methods to narrow the lines sufficiently to obtain spectral resolution. The 2D spin-diffusion CRAMPS spectrum was first recorded by Caravatti et al. [68] for blends of polystyrene (PS) and polyvinyl methyl-ether (PVME). There are other methods to generate an initial nonequilibrium polarization based on differences in linewidth or relaxation times. The reader is referred to the excellent book of Schmidt-Rohr and Spiess [67] for an overview. 

Fig. Phase diagram of the mixture polystyrene and polyvinyl methyl ether, molecular weights being = 62700 (PVME) and Mw = 60(W0 (PS), as obtained from light scattering. The lower curve describes the miscibility gap binodaF, coexistence curve ), the upper curve describes the spinodal curve, which touches the coexistence curve in the critical point. The shaded region in between binodal and spinodal is believed to describe homogeneously mixed metastable one-phase states. From Snyder et al. [27]. b Phase diagram for polyisoprene-poly(ethylene-propylene) with molecular weights of 2000 and 5000, respectively. From Cumming et al [70]...

Polyquaternium-11 (quaternium-23—Gafquat) is a copolymer of vinyl pyrrolidone and dimethylaminoethyl melliacrylate quaternized with dimethyl sulfate. This polymer is related to the quaternized copolymer of PVP depicted in Table 7-2. One mousse product in retail sale contains both of these cationic polymers. Others contain one cationic polymer and either a neutral or an anionic resin such as polyvinyl pyrrolidone and vinyl acetate copolymer, or a resin such as the butyl ester of polyvinyl methyl ether, a maleic anydride copolymer. 

Polyvinyl - methyl- ether Vinyl chloride polymers Urea- and melamineform-aldehyde condensates (uncured) Crosslinked (cured, vulcanized) polymers... 

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