Design and Synthesis of Polysiloxane Based Side Chain Liquid Crystal Polymer for Improving the Processability and Toughness of Magnesium Hydrate/Linear Low-Density Polyethylene Composites

Fluorine-Containing Flow Modifier for BN/PPS Composites Enabled by Low Surface Energy

In this study, a fluorine-containing flow modifier (Si-DF) with low surface energy is successfully synthesized, which is applied to fabricate ideal electronic packaging materials (BN/PPS composites) with high thermal conductivity, excellent dielectric properties, processability, and toughness by conventional melt blending. Si-DPF is located at the interface between the BN fillers and the PPS matrix, which not only improves the dispersion of BN fillers but also strengthens the interaction. With the help of 5 wt% Si-DF, BN/PPS/Si-DF (70/25/5) still exhibits the high thermally conductive coefficient (3.985 W/m·K) and low dielectric constant (3.76 at 100 MHz) although BN fillers are loaded as high as 70 wt%. Moreover, the sample processes a lower stable torque value (2.5 N·m), and the area under the stress-strain curves is also increased. This work provides an efficient way to develop high-performance polymer-based composites with high thermally conductive coefficients and low dielectric constants for electronic packaging applications.

Rheology and Processing of Polymers

I am so glad to share with you our Special Issue entitled 'Rheology and Processing of Polymers', which covers the latest developments in the field of rheology and polymer processing, highlighting cutting-edge research focusing on the processing of advanced polymers and their composites [...].

Grafting of thermotropic fluorinated mesogens on polysiloxane to improve the processability of linear low-density polyethylene

In this study, a series of polysiloxane grafted with thermotropic fluorinated mesogens (TSCPFLCP) is designed and synthesized. The TSCPFLCP exhibits a typical smectic liquid crystal phase, and shows a high thermal decomposition temperature at 335.6 °C. After blending with LLDPE, the balance melt torque of LLDPE/TSCPFLCP is decreased by 42% at 0.5 wt% TSCPFLCP, and the corresponding power law index is increased to 0.45. The flowing activation energy of the optimized LLDPE/TSCPFLCP blend is lower than that of pure LLDPE at the same shear rate, indicating that TSCPFLCP reduced the sensitivity of the apparent melt viscosity of LLDPE to both shear rate and temperature. This contributes to the broadening of the LLDPE processing window. On the other hand, TSCPFLCP is also found beneficial in ameliorating melt fracture during LLDPE extrusion. Furthermore, the mechanical properties of LLDPE/TSCPFLCP blends, such as tensile strength, elastic modulus and elongation at break, are also enhanced significantly at 0.5 wt% TSCPFLCP. Altogether, TSCPFLCP has been proven an effective processing aid to improve the processability and toughness of LLDPE.