Instron capillary rheometer

Melt flow rheology measurements were obtained on the MBAS polymer using an Instron capillary rheometer. The data reported were obtained using an 0.056-inch capillary, 90° included angle, with an L/D of 36. In Figure 5 the maximum shear stress (lb/in2) is plotted vs. the apparent shear rate (sec 1). The apparent viscosity (lb-sec/in2) vs. tem-... 

The density of the polymer at 25°C was obtained by using a molded disk, 0.125 in thick and 2 in in diameter. The melt density at processing temperature was obtained with an Instron Capillary Rheometer with plugged exit. The isothermal compaction at meltprocessing temperature was conducted at a plunger speed of 0.05 in/min with attainable pressures up to 25,000 psi. 

Jerman and Baird recently conducted rheological studies on the same copolymers using an Instron capillary rheometer. They also measured die swell and entrance pressures. They observed that the viscosity of the 60 mole % HBA/PET copolymer was two orders of magnitude lower than that of PET when compared at the same temperature of 285 °C, which is similar to the results reported earlier by Jackson and Kuhfuss Die swell of the copolymers was highly temperature dependent. In general,... 

Rheometrv. The following rheometers were used in this study An Instron capillary rheometer, a Rheometries mechanical spectrometer, used in both cone and plate mode as well as in the biconical mode, and a Brabender Plastograph (4). 

Rheological and Tensile Properties. Melt rheological measurements were made on an Instron Capillary Rheometer (0.993" L X 0.05014" D) at a temperature of 200°C and at various shear rates corresponding to crosshead speeds of from 0.005 in./min to 20 in./min. Measurements were also made with an Instron TM Model (0.05034" D X 1.0074" L) at 200°C and at various shear rates corresponding to crosshead speeds of from 0.006 in./min to 10 in./min. 

The melt viscosity data were obtained in a conventional manner using an Instron capillary rheometer over the temperature range of 180-240°C. The capillary had a 90° entry angle, and it was 5 cm long and 0.125 cm in diameter. The well known equations were used to calculate apparent viscosity. Shear rates at the wall, calculated assuming a Newtonian fluid, were corrected for nonparabolic velocity profile using the Rabinowitch equation. No correction was made for entrance effect because of the length-to-diameter ratio of the capillary used. 

Shown in Figure 6 is a plot of the viscosity of samples 3 and 5 plotted as a function of temperature. The viscosities were measured using an Instron Capillary Rheometer at a shear rate of 450 sec, The extracted solvent solubility parameters for samples 3 and 5 were 8.46 and 8.79 respectively. Figure 6 shows that the... 

A systematic study of the basic rheological properties for a wide variety of polypropylene melts has been made by Minoshima et al. [89]. These authors measured shear viscosities at low shear rates in a Rheomatrics mechanical spectrophotometer and at high rates in an Instron capillary rheometer. The principal normal stress difference, Ni, was measured in the mechanical spectrophotometer with a cone and plate device. The elongational viscosity, of special importance to fiber formation, was measured in an apparatus built by Ide and White [90],... 

The capillary experiments were done using an Instron Capillary Rheometer, Model TFD. For suspension I five capillaries were used with a constant L/D of 57.6 and diameters of 1.32,1.59, 1.98,2.52 and 3.05 mm. For suspension II four sets of capillaries with L/D ratios of 0, 19.2, 38.4 and 57.6 were used. In each set there were three capillaries with diameters of 1.32,1.59 and 1.98 mm. Capillaries with constant L/D, but varying diameters are needed to determine the slip velocity at the wall (12), whereas capillaries with constant diameter, but varying lengths are needed to determine the exit and entrance effects (13). 

The copolymers were extruded into monofilaments using an INSTRON capillary rheometer. The extrudates were drawn in two stages at about 54 C and then about 74 C using draw ratios of about 4.5 and 1.3X, respectively. After annealing, tensile properties were measured (Table 11). 

The copolymers were extruded using an INSTRON capillary rheometer. The extrudate filaments were annealed at room temperature from 2 hours to about one week prior to orientation. Fibers were drawn in a two stage glycerine bath, and annealed at 80° for 6 hours at 5% relaxation. The tables above summarize the data for these copolymers (Tables 12, 13 and 14). 

An Instron capillary rheometer (Model 3211) was used to measure the rheological properties. A capillary die of diameter D=0.00127m and a length to diameter ratio, L/D, of 28.7 was used. Measurement was done at 330 X and 350 °C for all PAI-l/LCP blends, but only for the 10% and 25% LCP concentration blends with PAI-2 since at all other concentrations a poor mixing was noticeable. 

JOHNSON, T.W. and O SHAUGHNESSY, M.T. Measurement of temporary and permanent shear with the instron capillary rheometer, SAE 1977, Paper No. 770377. 

Melt viscosities were determined with an Instron capillary rheometer. 

Coimnercially available instruments such as tire Monsanto Automatic Rheometer and the Instron Capillary Rheometer are examples of equipment which extrude the polymer through a capillary with a circular orifice using a pltmger at constant speeds. The principal features of this rheometer are shown schematically in Figure 3.3. 

The aromatic poly(anhydride)s were also extruded into fibers. For example, a sample of poly[l,4-bis(p-carboxyphenoxy)butane] exhibiting a melting point of 190°C was extruded using an Instron capillary rheometer equipped with a 40-mil die with an L/D of 25. 

Method 1 scosity versus shear data was generated by the authors using the Weissenberg Rheogoniometer R19 in the lower-shear-rate regkm (10 -l(P/s) and on the Instron Capillary Rheometer Model 3211 in the higher shear-rate region (10-l(f/s). 

FIG. 12 Plot of apparent viscosity r/ vs apparent shear rate / for HDPE at 230°C L /D = 40.1, Instron capillary rheometer II, specially designed capillary rheometer III, first non-Newtonian region IV, second Newtonian region V, second non-Newtonian region. (From Ref. 31.)... 

FIG. 18 Viscosity vs shear stress obtained by the Instron capillary rheometer for samples of LHDPE (curve 1) and LDPE (curve 2) at 190°C. (From Ref. 25.)... 

Figure 5.3 (b) Apparent viscosity versus apparent shear rate for HDPE at 230 "C LjD = 40). I Instron capillary rheometer II specially designed capillary rheometer IE first non-Newtonian region IV second Newtonian region V second non-Newtonian region [2]... 

The master rheogram for PP shown in Fig. 4.15 involves data from three sources [30,33,50] and includes 180 data points (Table B1 of Appendix B). Similar to the case of LDPE, one set of data was generated on the Weissenberg Rheogoniometer and Instron Capillary Rheometer using three different grades of PP, each at three different temperatures. These data were complemented by viscosity versus shear data obtained on different grades of PP from two different manufacturers. One set was obtained courtesy of J.P. Whelan, Amoco Chemical Cor-... 

Figure 11.4 gives log versus logo plots for a 70/30 PMMA/PS blend at 210, 220, and 230 "C, using data obtained from a cone-and-plate rheometer and from a plunger-type capillary rheometer (Instron capillary rheometer). Similar plots were obtained for 50/50 PMMA/PS blend and also for 30/70 PMMA/PS blend... 

Figure 12.6 Plots of log r] versus log y at 170 °C for neat PS (O, ) and carbon-black-filled PS composites with varying amounts of carbon black (wt %) ( , ) 5, (V,T) 10, (A, A) 20, and (O, ) 25, where filled symbols represent data obtained using a cone-and-plate rheometer, and open symbols represent data obtained using an Instron capillary rheometer with end correction. (Reprinted from Lobe and White, Polymer Engineering and Science 19 617. Copyright 1979, with permission from the Society of Plastics Engineers.)...

GR filled with 0.1 volume fraction of carbon black, and (3) GR filled with 0.2 volume fraction of carbon black, where the symbol O represents data obtained using an Instron capillary rheometer with end correction, the symbol A represents data obtained using creep measurement, and the symbol represents data obtained using a sandwich rheometer. (Reprinted from Montes et ah. Journal of Polymer Engineering 5(3) 209. Copyright 1985, with permission from Freund Publishing House.)... 

In analyzing the viscosity data, which were obtained using a plunger-type capillary rheometer (Instron capillary rheometer), for PS melts solubilized with CO2 or PCs (1,1-difluoroethane or l,l,l,2-teU afluoroethane) at elevated temperatures, Kwag et al. (1999) defined the pressure shift factor a by... 

The processing and properties of HDPE rods produced by solid state extrusion will be briefly described for more detail, the reader is referred to the original papers (6-8) and an extensive review by Zachariades, et al. (9). The polyethylene used was a duPont grade Alathon 7050 Mw = 57,000, Mw/Mn = 3. Melt crystallized billets were prepared by melting at 160 C and subsequent crystallization under the combined effects of temperature and pressure. The billets were extruded through a conical brass die, with an included entrance angle of 20°, in a 1 in. bore Instron capillary rheometer. 

This development involves the extrusion of a compacted powder billet prepared and extruded below the melting point. The powder is loaded into the 3/8" diameter barrel of an Instron capillary rheometer that is plugged at one end. A moderate pressure ( 0.23 GPa) is applied to compact the powder into a coherent billet. This billet is then extruded in the conventional manner giving a translucent coherent strand. 

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