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According to the six-state scheme proposed by Vacatello and Flory, the mean-square dipole moments <M 2 >/x (x: number of monomeric units) of poly(methyl methacrylate) (PMMA) chains and their temperature dependence dln<M 2 >/dT were calculated by the matrix algebra method of rotational isomeric state theory. To take account of the orientation effect of polar ester groups,...
A new nanocomposite—disorderly exfoliated layered double hydroxides/poly(methyl methacrylate) (LDHs/PMMA)—was prepared by a two-stage process with an in situ bulk polymerization of methyl methacrylate (MMA) in the presence of 10-undecenoate intercalated LDH (LDH-U). The LDH-U was prepared using the co-precipitation method. The structural and compositional details of the LDH-U were determined by X-ray...
Interpenetrating polymer networks (IPNs) combining polyisobutene (PIB) and poly(methyl methacrylate) (PMMA) networks were prepared using a in situ strategy. PIB networks were formed by isocyanate—alcohol addition between the hydroxyl end groups of telechelic dihydroxy-polyisobutene and an isocyanate cross-linker, catalyzed by dibutyltindilaurate (DBTDL). PMMA networks were obtained from free-radical...
Poly(methyl methacrylate) composites reinforced with natural protein biofibers from chicken feathers were prepared and evaluated through a series of tensile tests. Afterward, the samples were analyzed by optical and scanning electron microscopy studies, to obtain a clear picture of the tensile-induced damages.The hydrophobic nature of keratin fiber produces an excellent compatibility between fibers...
Physical aging of amorphous poly(methyl methacrylate) has been studied by low frequency Raman scattering, broad-band dielectric spectroscopy, low frequency high resolution mechanical spectroscopy and differential scanning calorimetry. The material was subjected to different thermal histories by isothermal aging. A consistent relationship between the changes caused by the physical aging in nanostructure...
In the present study, we apply a white light interferometric methodology to study sorption of moisture and methanol vapor in thin films of poly(2-hydroxyethyl methacrylate) [PHEMA] and poly(methyl methacrylate) [PMMA], supported on oxidized silicon wafers. The measured equilibrium thickness expansion of each film, exposed to different activities of the vapor penetrant, is used to determine the sorption...
The structure and properties of highly stereoregular isotactic poly(methyl methacrylate) (it-PMMA) and syndiotactic poly(methyl methacrylate) (st-PMMA) blends with crystalline stereocomplex formed by supercritical CO 2 treatment at temperatures ranging from 35 to 130°C were investigated by means of differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and dynamic mechanical...
Well-defined poly(methyl methacrylate)–silica nanocomposites were produced by “grafting through” using reversible addition–fragmentation chain transfer (RAFT) polymerization. The surface of silica nanoparticle was modified covalently by attaching methacryl group to the surface using 3-methacryloxypropyldimethylchlorosilane. Polymerization of methyl methacrylate (MMA) using the 4-cyano-4-(dodecylsulfanylthiocarbonyl)sulfanyl...
Poly(methyl methacrylate)/zirconia (PMMA/ZrO 2 ) nanocomposites with ZrO 2 content as high as 15wt% were prepared by modifying non-aqueous synthesized ZrO 2 nanoparticles with methacryloxypropyltrimethoxysilane (MPS) in tetrahydrofuran, dispersing MPS-functionalized ZrO 2 nanoparticles in MMA and following in situ bulk polymerization with controlled pre-polymerization...
A series of poly(methyl methacrylate)/montmorillonite (PMMA/MMT) nanocomposite were prepared by successfully dispersing the inorganic nanolayers of MMT clay in an organic PMMA matrix via in situ photoinitiated free radical polymerization. Methyl methacrylate monomer was first intercalated into the interlayer regions of organophilic clay hosts by “click” chemistry followed by a typical photoinitiated...
In this study, 2-methacryloxyethyl phenyl phosphate (MEPP), a phosphorus-containing flame retardant, was synthesised via the esterification of phenyl dichlorophosphate (PDCP) with 2-hydroxyethyl ethylene methacrylate (HEMA), followed by hydrolysis. A two-stage bulk polymerisation process prepared MEPP/methyl methacrylate (MEPP/MMA) copolymers containing various amounts of MEPP. The condensed-phase...
In this paper it is shown that elastic properties of a poly(methyl methacrylate) melt in the linear range of deformation are more significantly influenced by the addition of silica nanoparticles than viscous ones. The effect is the strongest in the steady-state which is reached at several thousand seconds. That is the reason why the often used dynamic-mechanical experiments are not a very suitable...
The synthesis of micron-sized polymer particles with a core-shell pomegranate-like morphology is presented. The proposed polymerization technique takes advantage of a reaction-induced micro-phase separation within a suspended organic liquid droplet containing monomer, a chemical initiator, a steric stabilizer, and a poor solvent for the polymer. With an increase in monomer conversion, the monomer...
For the first time poly(methyl methacrylate) (PMMA) nanocomposites based on a synthetic shear-stiff, mica-like K-fluorohectorite clay were prepared by melt -compounding. Besides stiffness, this new synthetic type of clay offers very high aspect ratios above 600 after exfoliation, whereas a tailored surface modification of the clay yielded a good compatibility to the matrix material. The influence...
The effects of network structure of crosslinked poly(methyl methacrylate) (PMMA) discs on dynamic penetrant transport behavior were investigated through gravimetric integral sorption studies. Samples of P(MMA-co-(EG) x DMA) were synthesized via an iniferter-mediated, thermally-initiated free radical polymerization procedure to produce polymers with controlled variations in network structure...
Polymer blends and alloys represent an interesting approach to implement bio-based poly(l-lactic acid) (PLLA) into high-value applications. Here, a re-evaluation of the miscibility extent between both biobased PLLA and petro-based poly(methyl methacrylate) (PMMA) is proposed in order to tune morphologies and properties of resulting blends upon either a solvent-casting method or a twin-screw extrusion...
Novel, star-shaped multifunctional poly(methyl methacrylate) (PMMA) macromonomers with well-defined average number of pendant methacrylate groups were synthesized by copolymerizing MMA with 2-hydroxyethyl methacrylate (HEMA) via quasiliving ATRP with a tetrafunctional initiator in methanol at 10 °C, followed by methacrylation of the hydroxyl groups of the HEMA units. The resulting tailor-made poly(methyl...
Poly(methyl methacrylate) (PMMA) monoliths with a three-dimensional continuous interconnected porous structure in a single piece were fabricated via thermally induced phase separation (TIPS) by utilizing unique cosolvency toward PMMA. We found that PMMA was soluble in a mixture of non-solvents (ethanol and water) at 60 °C. Cooling the solution resulted in formation of a monolith having interconnected...
Fracture-induced mechanochemical activation is achieved for the first time in a structural engineering polymer. Rubber toughened PMMA is lightly cross-linked (1.0 mol%) with the mechanophore spiropyran by free radical polymerization. Single Edge Notch Tension tests are performed on the spiropyran-linked material and a distinct change in color and fluorescence is detected at the crack tip, indicating...
The phase behaviors of poly(methyl methacrylate) (PMMA) and cross-linked PMMA gel in the mixtures of water and alcohol (ethanol, 2-propanol, and t-butanol) were investigated at three different temperatures. Phase separation temperature was determined through thermo-optical analysis (TOA) and the swelling transition of PMMA gel was measured by a photon correlation spectroscopy (PCS) technique. All...
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