Monitoring nonisothermal crystallization of thermoplastic polymers using a quartz crystal resonator

Abstract

A new monitoring device for the nonisothermal crystallization of thermoplastic polymers, polyethylene, polypropylene, polystyrene, and polyamide, is developed utilizing a quartz crystal resonator, and its performance is evaluated by comparing the measurements with the results of DSC thermoanalysis and microscopic observation. The experimental results of four different polymers indicate that the variation of resonant freency of the quartz crystal resonator is a good means to monitor the crystallization process. Though the measurements of melting and crystallization are close to the DSC outcome, more deviation is observed with the new device. The change in crystalline morphology during the crystallization process is also detected from the slope changes of the frequency decrease. In comparison with the microscopic observation of polymer films, it is found that the processes of nucleation and crystal growth in nonisothermal crystallization can be explained with the variation of the resonant frequency of the quartz crystal resonator. In addition, crystallization kinetics is modeled with the Avrami equation.

Measurement of thermal property of polystyrene using dual quartz crystal resonators

“…A similar device using single quartz crystal resonator has been proposed in Kim et al [12], but the detection of the morphological change of polymer material was more difficult than this dual resonator system. Though the proposed device using dual quartz crystal resonators is simple and easy to construct, its performance is comparable to the DSC.…”

“…This sensitive detection has been used to measure the adsorbed amounts of a specific components in gas [4,5] and liquid phases [6]. It also detects the beginning moment of crystal formation in crystallization processes [7][8][9][10] and the polymerization degree in UV polymerization [11,12]. When a thin film of polymer is coated on the electrode surface of the quartz crystal resonator, the viscoelasticity variation of the film due to its temperature change can be detected by monitoring the resonant frequency of the resonator [13,14].…”

Lityum Metaborat Dihidratın Difüzyon Katsayısının Belirlenmesi

“…Kristalizasyon prosesi kullanılarak çok faklı maddelerin endüstriyel olarak üretimi gerçekleşmektedir. Kristalizasyon polimer üretiminde [3][4][5], moleküler cam üretiminde [6], vitamin üretiminde [7] ve birçok 200 inorganik tuzun üretiminde [8][9][10][11][12] yaygın olarak kullanılmaktadır [13][14][15]. Fakat kristalizasyon işlemini tek başına değerlendirmek oldukça basit gibi görünse de herhangi bir maddenin kristallenmesi için aşırı doygunluk, nükleasyon ve kristal büyümesinin gerçekleşmesi gerekmektedir.…”

In-Line Measurement of Water Content in Ethanol Using a PVA-Coated Quartz Crystal Microbalance

“…From the variation of micro-rheology the kinetic rate of photopolymerization was measured to analyze polymerization kinetics [ 13 , 14 ]. The thermal properties of polymers were also measured from the change of visco-elasticity of the QCM [ 15 , 16 ].…”