Toughened poly methyl methacrylate

D. E. J. Saunders, Deformation and fracture of rubber-toughened poly(methyl methacrylate), PhD thesis, Victoria University of Manchester, 1990... 

Poomalai, R, Varghese, T. O., and Siddaramaiah. 2008. Investigation on thermoplastic CO poly (ether-ester) elastomer toughened poly (methyl methacrylate) blends. Journal of Applied Polymer Science 109(6) 3511-3518. 

Elloappan, V., El-aasser, M.S., Klein, A., Daniels, E.S., Roberts, J.E., and Pearson, R.A. (1994) Effect of the core/shell latex particle interphase on the mechanical behavior of rubber-toughened poly (methyl methacrylate). J. Appl. 

It is intended to toughen poly(methyl methacrylate) (PMMA) by the addition of particles of rubbery poly[(n-butyl acrylate)-co-styrene] made by emulsion polymerization. In order to retain the good optical clarity of the PMMA it is necessary to match the refractive indices, n, of the PMMA and copolymer particles. Estimate the relative proportions of the two comonomers required in the particles given that at room temperature the refractive index of PMMA is 1.489 and n is 1.466 for poly(n-butyl acrylate) and 1.591 for polystyrene. Would you expect the material to retain its clarity if the temperature were changed from ambient ... 

Fig. 5.66(b) shows a series of stress-strain curves for samples of rubber-toughened poly(methyl methacrylate) (RTPMMA) containing different weight fractions Wp of toughening particles. It can be seen that... 

Fig. 5.66 Stress-strain curves for rubber-toughened polymers, (a) Polystyrene (PS) and high-impact polystyrene (HIPS) (after Bucknall). (b) Rubber-toughened poly(methyl methacrylate) showing the effect of the weight fraction of rubber particlesy Wp (courtesy D.E.J. Saunders).

He, C., Donald, A.M. Morphology of a deformed rubber toughened poly(methyl methacrylate) film under tensile strain. J. Mater. Sci. 32, 5661-5667 (1997)... 

PIB-toughened poly(methyl methacrylate) (PMMA) networks have been reported in which the PIB domains are covalently bound to a PMMA matrix [26]. The synthesis involved a macromonomer approach where a combination of radical and cationic polymerization techniques were used. Methacrylate tri-telechelic PIBs were prepared by living cationic polymerization followed by end functionalization and used in free-radical solution copol)mierization with various amounts of MMA. Scheme 14 represents the general reaction pathways for the synthesis of network. 

SBM) as a compatibilizer. As a result of the particular thermodynamic interaction between the relevant blocks and the blend components, a discontinuous and nanoscale distribution of the elastomer at the interface, the so-called raspberry morphology, is observed (Fig. 15). Similar morphologies have also been observed when using triblock terpolymers with hydrogenated middle blocks (polystyrene-W<9ck-poly(ethylene-C0-butylene)-Wock-poly(methyl methacrylate), SEBM). It is this discontinuous interfacial coverage by the elastomer as compared to a continuous layer which allows one to minimize the loss in modulus and to ensure toughening of the PPE/SAN blend [69],... 

Rubber-Toughened Acrylic Molding Materials. The materials were prepared by blending the toughening particles with Diakon LG156 (supplied by ICI Acrylics), which is poly[(methyl methacrylate)-co-(n-butyl acrylate)] (92... 

The impact properties of poly(methyl methacrylate) (PMMA) may be improved by mechanical blending of small rubber particles with the matrix. Several authors have investigated the toughening mechanisms of these materials, which at present are only partially understood. In 1989, Mauzac and Schirrer (1) studied the effect of the rubber particles at the crack tip. They looked at particle volume fractions that ranged over five decades of concentra-... 

The different basic mechanisms shown in Figure 19 are valid for other toughened polymers as well. For example, the mechanism in Figure 19 is decisive for rubber-toughened poly(vinyl chloride) (37), polycarbonate, 38, 39), poly(methyl methacrylate) 40, 41), and rubber-toughened epoxies 42, 43). 

Another interesting three-component LIPN consists of crosslinked polyorganosiloxane (tet-raethoxysilane as crosslinker) as the first stage, swollen by butyl acrylate monomer (allyl methacrylate as crosslinker) and then polymerized to form the second component, and finally, poly(methyl methacrylate) was grafted onto the IPN core as the shell layer [Isao et al, 1992], Such kind of LIPNs are found to be a good impact modifiers in thermoplastics i.e., they are toughened by the addition of finely divided low phase. 

Poomalai, R, Ramaraj, B., and Siddaramaiah. 2007. Poly (methyl methacrylate) toughened by ethylene-vinyl acetate co-polymer Physico-mechanical, thermal and chemical properties. Journal of Applied Polymer Science 104 3145-3150. 

Cho Cho, K. W., Yang, J. H., Park, C. E. The effect of rubber particle size on toughening behaviour of rubber-modified poly(methyl methacrylate) with different test methods. Polymer 39 (1998)... 

The brittle characteristics of poly(methyl methacrylate) may be improved by copolymerization of small amounts of ethyl or butyl methacrylate or other monomers, and addition of small amounts of butadiene-styrene rubber (89). The latter practice, of course, is similar to the use of SBR elastomers to toughen polystyrene see Section 13.10.1. 

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