The internal plasticization of PVC by displacement of chlorine with phthalate-based thiol additives, that is, the covalent attachment of the plasticizer to the PVC chain, is described for the first time. Using this methodology, a good plasticization efficiency is achieved although flexibility is reduced compared with that of commercial PVC-phthalate systems. However, the migration is completely suppressed. This approach may open new ways to the preparation of flexible PVC with permanent plasticizer effect and zero migration.
A synthetic approach for the preparation and linkage of functionalized plasticizer molecules to PVC is described. The synthesis of this four-step procedure is economically and ecologically viable because it is based on trichlorotriazine as inexpensive starting material; the reactions can be carried out one-pot with quantitative yields and without need of final purification of the products. The approach is furthermore highly versatile and allows for the preparation of a large number of different plasticizers with properties that may be adjusted to a broad range of applications from highly flexible to semirigid.
A porous polymer
containing a fluorophenylphenanthroimidazole core was easily prepared
via one-pot Suzuki–Miyaura cross-coupling reactions under microwave
heating. These new metal-free polymers have demonstrated heterogeneous
photocatalytic activity toward aza-Henry reaction with reasonable
recyclability. Their preparation require a minimal workup to build
porous networks with control over the apparent surface area and pore
volume from suitable molecular building blocks containing 2-(1H-phenanthro[9,10-d]imidazol-2-yl)-3,5-difluorophenol
(PhIm-2F), as rigid and multitopic node, which afforded a conjugated
porous polymer (CPP-PhIm-2F). A series of fluorinated ligands have
shown their capability in the preparation of soluble and supported
cationic Ru(bpy)2(F-phenanthroimidazole) complexes by reaction
with Ru(bpy)2Cl2 and demonstrating a beneficial
effect of two fluorine atoms on the photocatalytic effect.
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