Simply Prepared Dual-Initiating Bis-Phosphonium Ylide-Based Lewis Pairs for Efficient Synthesis of Alkyl (Meth)acrylates (Co)polymers

The development of simply prepared catalysts for efficient and controlled polymerization is an important research challenge in polymer chemistry. Here, six newly designed dual-initiating bis-phosphonium ylide Lewis bases (LBs) with different linker lengths were prepared in a one-step process. When combined with organoaluminum, these LBs enable rapid and living polymerization of five alkyl (meth)acrylates, including methyl methacrylate (MMA), ethyl methacrylate (EMA), benzyl methacrylate (BnMA), n-butyl acrylate (nBA), and 2-ethylhexyl acrylate (EHA). Consequently, polymers with predictable molecular weights (Mn up to 155.1 kg/mol) and small Đ values (as low as 1.08) can be synthesized. By integrating the unique compounded sequence control (CSC) strategy of Lewis pair polymerization (LPP) and dual-initiating character of these bis-phosphonium ylide LBs, undecablock copolymers of different monomers were prepared through three sequential monomer mixture feeding while maintaining excellent controllability over polymer structures as demonstrated by gel permeation chromatography (GPC) and diffusion ordered spectroscopy (DOSY) analyses. Furthermore, a series of all-acrylic-based thermoplastic elastomers (TPEs) with different hard and soft segments were also synthesized in one-step, and the copolymer structures and glass transition temperature (Tg) effects on the mechanical properties of the TPEs were investigated. Hence, the aforementioned outcomes underscore the efficiency and robust capability of our newly developed bis-phosphonium ylide-based LPP strategy in polymer synthesis

Determination and Correlation of the Solubility of Sodium Naphthalene-1,5-disulfonate in Five Pure Solvents and Three Binary Solvent Systems at the Temperature Range from 283.15 to 323.15 K

Experimental solubility data of sodium naphthalene-1,5-disulfonate in five neat solvents (water, methanol, ethanol, 2-propanol, acetone) and three binary solvent systems (water + ethanol, water + 2-propanol, water + acetone) at different temperatures from 283.15 to 323.15 K were determined by the gravimetric method. The experimental results showed that three kinds of polymorphs appeared in the investigated solvent systems, and the solubility of sodium naphthalene-1,5-disulfonate all increased with increasing temperature and water content. According to the data measured, water was suitable to be the positive solvent, while methanol was considered to be a less-effective antisolvent due to its relatively large dissolving capacity. By means of our research, the solubility of sodium naphthalene-1,5-disulfonate in the neat solvents had a relation with the polarity of the solvents. The solubilities of sodium naphthalene-1,5-disulfonate were fitted by the modified Apelblat, Jouyban-Acree, van’t Hoff-Jouyban-Acree, and Apelblat-Jouyban-Acree models. The results showed that the four models can predict the experimental values very well