本實驗以小角度光散射法量測PNIPAM溶液，在不同溫度(當大於binodal temperature)的光散射強度得到time-resolved light scattering圖譜，採用phase dissolution方法，將發生相分離的PNIPAM水溶液達SD相分離(spinodal decomposition)穩態，進行逐步降溫，在不同等溫溫度下，進行光散射強度分析，透過此方法來了解相分離結構崩塌的溫度，當發生相分離時，會發生NG (nucleation and growth)和SD相分離，先將溶液的溫度恆溫在Tb< T <Ts達穩態，再升溫至T > Ts，進行逐步降溫後，利用兩種相分離在光散射強度圖譜中的不同，以此方法可得此PNIPAM水溶液的Ts以及Tb。

This experiment employs small-angle light scattering (SALS) to measure PNIPAM solutions. At different temperatures (above the binodal temperature), the scattering intensity is recorded to obtain time-resolved light scattering spectra. Using the phase dissolution method, PNIPAM aqueous solutions undergo spinodal decomposition to reach a steady state. The solution is then gradually cooled, and light scattering intensity is analyzed at various isothermal temperatures. This approach helps to understand the temperature at which the phase separation structure collapses. During phase separation, nucleation and growth (NG) and spinodal decomposition (SD) occur. The solution temperature is initially held constant at Tb < T < Ts to reach a steady state, then raised to T > Ts, and subsequently cooled gradually. By analyzing the differences in scattering intensity spectra between the two types of phase separation, this method allows for the determination of Ts and Tb for the PNIPAM aqueous solution.

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