Polyfmethyl methacrylate PMMA

Figure 6 (A) Non-isothermal chemiluminescence runs for oxidation of polystyrene (PS), polyethylene terephthalate) (PETP) and polyfmethyl methacrylate) (PMMA), in oxygen, heating rate 2.5°C/min. (B) Non-isothermal chemiluminescence runs for oxidation of polypropylene (PP), polyamide 6 (PA 6), poly(vinyl pyrrolidone) (PVP), polyethylene (PE) and polyamide 66 (PA 66), in oxygen, heating rate 2.5°C/min.

FIG. 13.28 Frequency-temperature correlation map for polyfmethyl methacrylate) (PMMA). Dynamic mechanical measurements are indicated by filled points and dielectric measurements by open points ... 

Trithiocarbonates (TTC) also offer an interesting alternative platform by dynamic covalent reshuffling reactions of TTC via a free radical mechanism shown in Fig. 15b. It was first introduced into polyfmethyl methacrylate) (PMMA) and polystyrene (PS) gels as a covalent crosslinker, which exhibited dynamic properties [64]. Following this, it was found that the C-S braids of TTC can be photostimulated, and high segmental mobdity of the polymer matrix obtained by RAFT copolymerization of -butyl acrylate (BA) and a TTC crosslinker can facilitate repetitive network repairs using UV radiation at 330 nm [64]. 

By lowering the experimental temperature, transition from normal dissolution to the type of dissolution without a gel layer was observed in the dissolution of polyfmethyl methacrylate) (PMMA) [27]. The temperature at which the gel layer disappeared was termed as the gel temperature. Ueberreiter and Asmussen [28] observed that polystyrene (PS) undergoes normal dissolution in most solvents owing to its low gel temperature. 

The appearance of a maximum in the chain length dependence of the characteristic ratio was first found by Yoon and Flory [60] in the RIS chain computations on atactic and syndiotactic polyfmethyl methacrylate)(PMMA). Yamakawa and Fujii [63] showed that their formula for the HW chain with <7o can be fitted accurately to the computed results of Yoon and Flory over dm almost entire range of chain length if the basic parameters of the HW chain are suitably chosen. A similar agreement in characteristic ratio between the HW (<7o = 0) and RIS chains was obtained for other flexible polymers. The choice of relation between the RIS chain model and the discrete chain whose continuous limit is the HW chain. 

Altuglas Acrylic, polyfmethyl methacrylate), PMMA sheets Societe Altulor SA/ Elf Atochem... 

Resarit Polyfmethyl methacrylate), PMMA powder Resart-IHM AG... 

Figure 13.6 Life cycle of polyfmethyl methacrylate) (PMMA)-containing products. MMA, Methyl methacrylate ACH, acetone cyanohydrin method TBA-DO, tertiary butyl alcohol (isobutylene) direct oxidation method TBA-DOE, tertiary butyl alcohol (isobutylene) direct oxidative esterification method C2, ethylene method TR, thermal recovery MR, material recycling. Modified from Kikuchi Y, Hirao M, Ookubo T Sasaki A. Design of recycling system for polyfmethyl methacrylate) (PMMA). Part 1 recycling scenario analysis. Int J Life Cycle Assess 20i4 i9(i) 120—9.

System for Automotive Thermoplastics Elastomeric Olefins (TEO) System for Automotive PolyfMethyl methacrylate) (PMMA) Plasticsl System for Automotive Polyester Plastics ... 

The mechanical properties of polyfmethyl methacrylate), PMMA, have been studied for quite a long time and, in addition to its industrial interest, PMMA constitutes a kind of reference material Indeed, among the amorphous linear polymers it represents an intermediate between the very brittle polystyrene and the tough bisphenol A polycarbonate considered in Sect. 4. Furthermore, as shown in [1] (Sect. 8.1), the molecular motions responsible for its large transition are precisely identified, as well as the nature of the cooperativity that develops in the high temperatme range of the jS transition. 

Problem 3.17 Calculate the solubility parameter for a methyl methacrylate-butadiene copolymer containing 25 mol % methyl methacrylate. The solubility parameter values for polyfmethyl methacrylate) (PMMA) and polybutadiene (PB) homopolymers, calculated from molar attraction constants, are, respectively, 9.3 and 8.4 (cal cm ). ... 

FIGURE 2.5 Reduced density versus temperature for polyfmethyl methacrylate) (PMMA) at 25°C by Sanchez-Lacombe lattice fluid theory. 

Methyl methacrylate (MMA) is by far the most important methacrylic ester monomer, accounting for 90% of the volume of methacrylic ester monomers. Polyfmethyl methacrylate) (PMMA) was first synthesized in 1928 in various laboratories, and was first brought to market in 1933 by Rohm Haas Co. under the trademark Plexiglas. ICI then reformed Rohm s method and commercialized MMA in 1937 by the acetone cyanohydrine (ACH) process,[l] which is still the most widely adopted technique even today. The world production capacity of PMMA has almost doubled in the past fifteen years, and overall global PMMA production capacity accounts for six hundred and fifty thousand tons per year. [3] It is predicted that starting from 2010, the demand for PMMA will rise by 3-5% annually and the demand of MMA is expected to steadily grow in the future.[3]... 

Until 2003, Chen s [28], Qu s [29-31], and Hu s [32] groups independently reported nanocomposites with polymeric matrices for the first time the. In Hsueh and Chen s work, exfoUated polyimide/LDH was prepared by in situ polymerization of a mixture of aminobenzoate-modified Mg-Al LDH and polyamic acid (polyimide precursor) in N,N-dimethylactamide [28]. In other work, Chen and Qu successfully synthesized exfoliated polyethylene-g-maleic anhydride (PE-g-MA)/LDH nanocomposites by refluxing in a nonpolar xylene solution of PE-g-MA [29,30]. Then, Li et al. prepared polyfmethyl methacrylate) (PMMA)/MgAl LDH by exfoliation/adsorption with acetone as cosolvent [32]. Since then, polymer/LDH nanocomposites have attracted extensive interest. The wide variety of polymers used for nanocomposite preparation include polyethylene (PE) [29, 30, 33 9], polystyrene (PS) [48, 50-58], poly(propylene carbonate) [59], poly(3-hydroxybutyrate) [60-62], poly(vinyl chloride) [63], syndiotactic polystyrene [64], polyurethane [65], poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] [66], polypropylene (PP) [48, 67-70], nylon 6 [9,71,72], ethylene vinyl acetate copolymer (EVA) [73-77], poly(L-lactide) [78], poly(ethylene terephthalate) [79, 80], poly(caprolactone) [81], poly(p-dioxanone) [82], poly(vinyl alcohol) [83], PMMA [32,47, 48, 57, 84-93], poly(2-hydroxyethyl methacrylate) [94], poly(styrene-co-methyl methacrylate) [95], polyimide [28], and epoxy [96-98]. These nanocomposites often exhibit enhanced mechanical, thermal, optical, and electrical properties and flame retardancy. Among them, the thermal properties and flame retardancy are the most interesting and will be discussed in the following sections. 

Experimental work was carried out with a two-dimensional mixer with various types of rotors. The experimental apparatus is shown schematically in Fig. 1. Variation of the mixing state with time at room temperature was followed using a videocamera. The brass mixer with a transparent plastic window polyfmethyl methacrylate) (PMMA) normal to the rotor axis is shown in Fig. 2a. One pressure transducer and four thermocouples (C-C) were set into the wall of the mixing chamber as shown in Fig. 2a to measure the temperature and pressure of the rubber on the wall. Three pressure transducers were attached to another plastic window at positions A, B, and C as shown in Fig. 2b to observe the mixing behavior in the reservoir. The shapes of rotors with wings used are shown in Fig. 3. These rotors were made of 19.5-mm-thick brass. The shapes in (a) and (b) type rotors in Fig. 3 are similar to the rotors used by Freakly and Patel (1985) and Min and White (1985), respectively. The (c), (d), (e), (0, and (g) type rotors are the new types. To transport the rubber in the reservoir easily, the rear part of these rotor wings were cut out either straight or concave. The (h) type rotor is the... 

Figure 2.5 (a) Structure functions, S q)s, for polyfmethyl methacrylate) (PMMA). The observed data from an X-ray diffraction measurement and that simulated using molecular modeling are shown. Li et al. [31]. Reproduced with permission of American Chemical Society, (b) A curvature in the chain to account for the splitting of the peak at 2.5 A . ... 

Furthermore, research has shown improved mechanical properties via nanotube orientation by melt drawing after melt compounding in a polyfmethyl methacrylate) (PMMA) matrix with low levels ( 1 wt%) of multiwall carbon nanotubes (MWNTs). ... 

The most popular polymers used to fabricate lab-on-a-chip structures are polyfdi-methylsiloxane) (PDMS), polyfmethyl methacrylate) (PMMA), high-density polyethylene, low-density polyethylene, polyamide 6, and the epoxy-based photoresist SU-8 (Becker, 2002). Particularly, PDMS has been widely reported for miCTofluidic systems because it has many favorable properties for prototypes fabrication the material is inexpensive, optically transparent to visible Ught, which makes it compatible with optical detection systems, and also biocompatible its molding procedure is safe and easy to learn and its flexibility allows the integration of elastomeric actuators and optical elements into devices. 

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