Question

Mode-coupling theory badly overestimates experimental measurements of this quantity by assuming it coincides with the onset of the hopping regime. This quantity is additive for blends of drugs and excipients like trehalose (“TREE-hull-ose”) according to the empirical Gordon–Taylor equation. (-5[1])The operational definition of this quantity, which is calculated from the location of the tan-delta or loss modulus peak in DMA, corresponds to a viscoelastic relaxation time of 100 seconds after a t–T (“T-T”) superposition. Anti-plasticizers stabilize organic films by reducing this quantity; (-5[1])otherwise, it increases asymptotically with molecular weight. The derivative (-5[1])of specific heat (-5[1])is discontinuous (-5[1])at this quantity’s x-value on a DSC trace. (10[1])Free volume expands, and entropy spikes, when a sample is heated past this point, allowing chains (10[1])to be (10[1])more flexible. (10[2]-5[1])For 10 points, (10[2])name this temperature (10[1]-5[1])at which polymers transition (10[1])from a (10[1])rubbery (10[1])state to a (10[1])viscous (10[1])state. (10[2])■END■ (10[2]0[3])

ANSWER: glass transition temperature [or T-sub-g; or glass transition point; prompt on temperature or T until “temperature” is read] (DMA is dynamic mechanical analysis. DSC is differential scanning calorimetry.)
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77%32%128.5

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