Association of stereoregular poly(methyl methacrylates). 6. Double-stranded helical structure of the stereocomplex of isotactic and syndiotactic poly(methyl methacrylate)

Synthesis and thermal characterization of polymethyl methacrylate

PMMA with molecular mass (PMMA Mw: 1.2×105) was synthesized through AIBN initiated free radical polymerization methyl methacrylate at 100 ± 1°C.The synthesized polymer was characterized through GPC coupled with RI detector in presence of THF as mobile phase at 1.0 mL/ min and simultaneous TG-DTA-DTG in nitrogen. TG data were used to investigate the non-isothermal kinetics of solid-state decompo...

Supramolecular helical structure of the stereocomplex composed of complementary isotactic and syndiotactic poly(methyl methacrylate)s as revealed by atomic force microscopy.

the underlying structure of language proficiency and the proficiency level

هدف از انجام این تخقیق بررسی رابطه احتمالی بین سطح مهارت زبان خارجی (foreign language proficiency) و ساختار مهارت زبان خارجی بود. تعداد 314 زبان آموز مونث و مذکر که عمدتا دانشجویان رشته های زبان انگلیسی در سطوح کارشناسی و کارشناسی ارشد بودند در این تحقیق شرکت کردند. از لحاظ سطح مهارت زبان خارجی شرکت کنندگان بسیار با هم متفاوت بودند، (75 نفر سطح پیشرفته، 113 نفر سطح متوسط، 126 سطح مقدماتی). کلا ...

Salvage of Infected Nasal Reconstruction with a Polymethyl Methacrylate Spacer

Total nasal reconstruction is a challenging multistage procedure. Infections can destroy the cartilage framework and seriously compromise the result. The use of polymethyl methacrylate with antibiotics as a spacer has been described in the treatment of skeletal infections. Using this same principle, the use of a polymethyl methacrylate with antibiotics spacer for an infected nasal reconstructio...

Tribological performance of polymethyl methacrylate as an aviation polymer

Polymethyl methacrylate (PMMA) is one of the most popular synthetic polymers in aircraft windshields as an alternative to glass, due to its lightweight, high transparency and impact-resistant characteristics. The erosion behavior of PMMA is critical when used as an alternative to glass in an aircraft windshield. This paper presents experimental data on the effects of particle size, velocity and...