Investigation of Polymer‐Filler Interactions in TiO₂‐Filled Poly(n‐alkyl methacrylates) by Low‐Field NMR Relaxometry

Abstract

Low‐field NMR relaxometry is sensitive to molecular mobility within well‐defined time windows and can thus be applied to study interactions between polymers and inorganic filler particles in composite materials. Volume fraction and dispersion of the filler influence the polymer chain dynamics, which also modify the macroscopic properties of the polymer composites. As model systems, TiO2‐filled poly(n‐alkyl methacrylates) with different side‐chain lengths and filler contents are prepared by melt mixing. Several 1H NMR relaxation parameters, which are sensitive and selective toward polymer–filler interactions, are investigated at a Larmor frequency of 20 MHz as a function of temperature. Both physical and empirical models are used to analyze the NMR data, and the results are compared with the aim of an unambiguous detection of polymer–filler interactions.

Polymer Crystallization Studied by Hyphenated Rheology Techniques: Rheo‐NMR, Rheo‐SAXS, and Rheo‐Microscopy

“…The flow and deformation behavior of polymer melts can be thoroughly studied using rheology, whereas low‐field NMR relaxometry (also called Time Domain (TD)‐NMR) is a powerful technique for the characterization of molecular dynamics in polymeric materials . To achieve a substantial insight into the interplay of these domains, especially under flow, these two methods were combined into a single set‐up (Figure a) .…”

“…The flow and deformation behavior of polymer melts can be thoroughly studied using rheology, whereas low-field NMR relaxometry (also called Time Domain (TD)-NMR) is a powerful technique for the characterization of molecular dynamics in polymeric materials. [80][81][82][83][84][85] To achieve a substantial insight into the interplay of these domains, especially under flow, these two methods were combined into a single set-up ( Figure 3a). [71] This approach is different from other Rheo-NMR set-ups, as its main purpose is the study of molecular dynamics rather than chemical structure via NMR spectroscopy or morphology via magnetic resonance imaging.…”

Polymer crystallinity and crystallization kinetics via benchtop 1H NMR relaxometry: Revisited method, data analysis, and experiments on common polymers

“…Analyzing decay curves is commonly referred to as NMR relaxometry, a sub group of NMR experiments in the time domain (TD NMR). Many materials with mobility contrast have been studied by 1 H NMR relaxometry in the past, e.g., fats [30,31], carbohydrates [32], rub bers [33,34], composites [35,36], and also semi crystalline poly mers [37e43]. For food grade oils and fats these studies have led to industrial standards for the determination of the solid fat content (SFC), which is frequently used for quality control [44,45].…”

Hyphenated low‐field NMR techniques: combining NMR with NIR, GPC/SEC and rheometry

“…Modern protocols for NMR data treatment, such as multivariate data analysis, are also employed in low‐field NMR . Some well‐known examples of applications using low‐field NMR include the study of droplet sizes in emulsions, the determination of molecular dynamics in polymeric materials and the quantification of hard/soft ratios in multicomponent materials …”

“…[11][12][13][14][15][16][17][18][19] Modern protocols for NMR data treatment, such as multivariate data analysis, are also employed in low-field NMR. [20][21][22][23][24][25][26][27] Some well-known examples of applications using low-field NMR include the study of droplet sizes in emulsions, [28][29][30][31] the determination of molecular dynamics in polymeric materials [32][33][34][35][36][37][38] and the quantification of hard/soft ratios in multicomponent materials. [2][3][4]39,40] Low-field NMR is a promising candidate for use as an online sensor in process analytics and control as a result of its design, robustness and simplicity.…”