Samples, solutions cast from

Sample Preparation. Samples for mechanical studies were made by compression molding the polymers at 150°C between Teflon sheets for 15 minutes followed by rapid quenching to room temperature in air. These will be referred to as PQ (press-quenched or simply quenched) samples. The thickness of the PQ samples was around 10 mils (0.25 mm). The thermal history of all of the PQ samples (HBIB, HIBI, and LDPE) were essentially the same. They were used within one week after they were pressed. Samples for morphology, SALS and SEM studies were prepared from toluene solutions. These films were cast on a Teflon sheet at 80 C from a 1% (by weight) solution in toluene. These films were about 5 mils in thickness. When the polymer films had solidified (after 5 hrs), they were stored in a vacuum oven at 80°C for two days to remove residual solvent. These samples will be designated by TOL (solution cast from toluene). 

The IR spectra were obtained with a Perkin-Elmer PE-467 grating spectrophotometer from about 4000-500 cm . Normal slit position and medium scan mode were used. Films of polymer samples were cast from CS2 solutions on NaCl windows. 

Fig. 19 TEM image of toroidal micelles from a PAA-PMA-PS triblock copolymer (A). This sample was cast from a solution with 0.1 wt% PAA99-PMA73-PS66 triblock copolymer, a THF water volume ratio of 1 2, and an amine acid molar ratio of 0.5 1 by addition of 2,2-(ethylenedioxy)diethylamine. The cast film was negatively stained with uranyl acetate. A schematical representation of theses micelles is also shown (B). Reprinted with permission from [279], Copyright (2004) American Association for the Advancement of Science...

Methods. Polyblend samples were prepared by solution casting from tetrahydrofuran (THF), or chloroform or by injection molding using a Mini-Max Molder by Custom Scientific Instruments. Specific experimental details are given elsewhere (9,10,11). 

Thin films with a thickness of 50 pm of a commercially available PS-PB-PS triblock copolymer (e.g. from BASF, 74% PS, 26% PB) are prepared by solution casting from a 3% solution in toluene onto TEFLON -foil, which is placed in a precleaned petri-dish. The solvent is slowly evaporated over a period of 2 weeks. Residual solvent is then removed and films are annealed under reduced pressure in a vacuum oven at 120°C (48 h). Finally, the films are removed from the support and are uniaxially stretched at a constant strain rate of 0.1 s 1 beyond the yield point at room temperature. ARM investigations are carried out on prestretched samples that are mechanically clamped or fixated by double-sided sticky tape onto the AFM sample holder. 

Optical Spectroscopy. Figure 7 shows the optical spectra of solution cast (from slowly evaporated methylene chloride solution) poly(, 8-nonadlyne) films which have been exposed to UV light (1600 uW/cm at 254 nm, under UHP argon purge) for various times. The macromonomer has no absorbance maxima In the region shown, whereas, samples with less than about 5 minutes exposure have two dlscernable maxima- at 575 nm and 630 nm. At low conversions (about 2 to 11... 

Film spectra were taken using thin films of polymer spun-cast on 1.6 mm thick fused silica flats, 25 x 25 mm square. All film samples were cast from xylene which had been previously dried over i)A molecular sieves. For the solution spectra, toluene was used after distillation from NaK alloy under Ar. The alkane solvents were obtained from a variety of sources and used without further purification. 

NMR spectra were obtained on a Varian EM360 or an A60, 60 MHz spectrometer in C Dg, CDClj or o-C H4Cl2 solutions. TMS was used as an Internal standard. For Infrared spectra, thin films of the samples were cast from CHCI3 solution on NaCl plates and the solvent evaporated under vacuum. Spectra were recorded on a Dlgllab FTS 14 FTIR spectrophotometer. 

Ternary blends prepared in THE, precipitated by MeOH, then dried. DSC at 20°C/min within T = 310-430K Samples by solution casting from THF in a Petri dish DSC at 20°C/min. T taken at onset. 

DCS at 20°C/min. Diverse phase diagrams Samples prepared by casting from CHClj DSC measurements at 20°C/min T < 530K T taken at half-height Samples cast from DMF into Petri dish DSC at 20°C/min to 190°C. Miscibility only for the GMA < 35.7 wt% in PMMA-GMA Samples hot cast from o-dichlorobenzene into Petri dish DSC at 20°C. Samples annealed at 200°C for 5 min THF solution precipitated by MeOH. DSC at 10°C/min T taken as mid-point in the inflection Samples either cast, precipitated from solution, or melt mixed at 250°C. DSC at 20°C/min T from second scan. Solution cast samples gave two T, whereas the other methods only one Melt mixing at 300°C. DSC at 20°C/min. T taken at onset... 

Mishra et al. [1994] and Bajpai et al. [1994] determined the microhardness of PMMA/PVDF and PMMA/PCTFE blends (Table 11.9) made by solution casting from dimethyl formamide solutions. The solutions containing the two polymers were heated at 110°C for 3 h and were poured into an optically plain glass mold to prepare pellets of the blends. The poured material was annealed at 75°C for 3 h. The samples were cut from the slowly cooled (24 h) pellets for this work. 

PCL (M 70,000-100,000) has been blended with a novolac (a low-molecular-weight condensation product of phenol and formaldehyde) (M =565) in some samples the novolac was crossUnked with hexamethylenetetramine (HMTA). Initial blends were prepared by solution casting from dichloromethane/ethanol (90/10) mixtures samples were dried at 50° C imder vacuum for 72 h. For curing purposes HMTA was added at 15 wt % relative to the novolac. 

Thermolysis of the Co-containing polymer films was carried out in vacuum, at 220°C unless otherwise stated. Samples are identified by the Co content (in wt.%) in the precursor film before thermolysis, as determined by X-ray fluorescence (XRF) analysis the suffixes "A" and "T" indicate samples as-cast from solution and after thermolysis, respectively. 

Figure 5 shows the major features of the Ting solution, for the Voigt/Kelvin model (Figure 5a) and the Maxwell model (Figure 5b). The elastic element has E = 2 MPa and the viscosity of the dashpot is selected to yield a relaxation time of r = 50 s. These values are similar to those of the poly(vinylethylene) sample freshly cast from...

The thermoreversibility of the monoesterification reaction between nonandiol or HTPB and EPR g-SA has been studied by using a calorimetric cell attached to a FTIR spectrophotometer. The stoichiometric reaction conditions chosen are ratio SA/OH, 1/1.5. The procedure was as follows the sample, after casting from solution onto KBr disks at room temperature under vacuum, was rapidly brought to 220°C and left at this temperature for 30 min such a procedure was chosen because at T > 200°C the esterification reaction does not occur at all [66] we can consider this situation as the zero reaction time (actually, as shown by the first spectrum of Fig. 12, a certain amount of ester is already present at T = 220°C, probably due to the time necessary to cast the film and to bring it to 220°C). 

Figure 2 The transmission electron micrographs of samples cast from solution containing 1 wt% of polymer, (a) the block copolymer BCl, and (b) the microsphere, MCI [24].

Films of purified PVCa were cast from methylene chloride solution on quartz plates. The solvent was allowed to slowly evaporate to give smooth, clear films with a thickness of ca. 5.0 nm. Contact angle measurements using water droplets were measured with a standard contact angle goniometer. Samples were photo-lysed in air with polychromatic light from a 150 watt xenon arc. Contact angles were measured after various times of irradiation to monitor the formation of oxidation products at the surface of the polymer films. 

Samples of /the polymers for physical evaluation were prepared by film casting from toluene solution at 90°C. and allowing the crystallization to occur by cooling the melt. It was observed that phase separation occurred in the melt in the case of the H2-BIB but not for the H2-BBB. These materials could also be compression molded at 1<40°C., but optimum results appeared to be obtained with the film-cast samples. 

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