High-pressure phase behavior data are reported for statistically random poly(ethylene-co-20.2 mol%-1-butene)(PEB10)in ethane and deuterated ethane from ambient temperature to 155°C and pressures to 130 MPa.The two cloud-point curves exhibit negative slopes in pressure-temperature(P-t)space with the PEB10-deuterated ethane curve at higher pressures than the curve in ethane.Data are also reported for statistically random deuterated PEB10(d-PEB10)in n-pentane,isopentane,neopentane,and cyclopentane.Solvent quality orders as cyclopentane>n-pentane>isopentane>neopentane,which is also the same ordering of the solvent critical temperatures.The d-PEB10-cyclopentane cloud-point curve has a steep positive P-t slope of approx=0.28 MPa·°C~(-1)near 200°C.The d-PEB10-n-pentane and isopentane curves also have positive P-t slopes of approx=0.16 MPa·°C~(-1)at temperatures between(approx=100 and 200)°C and pressures to approx=15 MPa.The curve for the d-PEB10-neopentane system is virtually flat at a fixed pressure of approx=20 MPa from(200 to approx=30)°C,where the curve changes abruptly to a positive slope of approx=1.65 MPa·°C~(-1).The positive-slope portion of this cloud-point curve represents solid+liquid to fluid transitions where the neopentane is the solid phase not the d-PEB10,which is amorphous.
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