A Forgotten Class of High TG Thermoplastic Materials: Anionic Copolymers of Styrene and 1, 1-Diphenylethylene

Monomer Sequence Control via Living Anionic Copolymerization: Synthesis of Alternating, Statistical, and Telechelic Copolymers and Sequence Analysis by MALDI ToF Mass Spectrometry

“…Previous studies suggest that a perfectly alternating copolymer of styrene and DPE will have a T g of approximately 180 °C, substantially higher than polystyrene which has a T g of about 100 °C . In the present study T g values (shown in Table ) were obtained by differential scanning calorimetry (DSC), which can be correlated with the corresponding copolymer composition: Xu and Bates have previously reported that the T g of poly(styrene- co -DPE) increases by 1.09 °C/wt % DPE, while Knoll et al found T g increases by 1.26 °C/wt % DPE . Plotting the experimental values of T g for copolymers of PSD-1 to -4 and PSD-7 to -9 versus wt % DPE shows that T g increases linearly by a value of 1.19 °C/wt % DPE (Figure ).…”

“…As well as being a monomer of interest from the perspective of monomer sequence control, DPE is also interesting in so much that it can dramatically increase the glass transition temperature ( T g ) of the resulting copolymers and allow T g to be tuned as a function of comonomer composition. − DPE is a bulky monomer and results in reduced chain motion and stiffening of the polymer backbone, in turn leading to polymers with higher values of T g . Previous studies suggest that a perfectly alternating copolymer of styrene and DPE will have a T g of approximately 180 °C, substantially higher than polystyrene which has a T g of about 100 °C .…”

Synthesis and Thermal Properties of Hydrogenated Poly(styrene-co-1,1-diphenylethylene) Copolymers

“…T g values for the h-S/DPE copolymers are plotted as a function of weight percent of hydrogenated DPE repeat units (h-DPE wt %) in Figure 4. Correlations between T g and composition for the unsaturated and saturated materials can be approximated by 6 who found that the T g of S/DPE increases by 1.26 °C/wt % DPE. This small difference (0.17 °C/wt %) might result from the smaller molecular weights employed here or possibly a different segment sequence distribution.…”

“…4,5 Significantly, Knoll and co-workers recently reported that the DPE monomer can be produced by a low-cost process. 6 In this note, we describe the preparation and complete catalytic hydrogenation of S/DPE copolymers as sketched in Figure 1. The product, hydrogenated poly(styrene-co-1,1-diphenylethylene) (h-S/DPE), exhibits T g values as high as 199 °C.…”

“…1,1-Diphenylethylene (DPE) can be copolymerized anionically with styrene to form poly(styrene- co -1,1-diphenylethylene) (S/DPE) copolymers with T g values as high as 175 °C. , Significantly, Knoll and co-workers recently reported that the DPE monomer can be produced by a low-cost process . In this note, we describe the preparation and complete catalytic hydrogenation of S/DPE copolymers as sketched in Figure .…”