Novel monomers 2-(N-methylacrylamido)ethylphosphonic acid, 6-(Nmethylacrylamido)hexylphosphonic acid, 10-(N-methylacrylamido)decylphosphonic acid, and 4-(N-methylacrylamidomethyl)benzylphosphonic acid have been prepared in good yields for use in dental adhesives. They have been fully characterized by 1 H-NMR, 13 C-NMR, 31 P-NMR, and by HRMS. All monomers are hydrolytically stable in aqueous solution. Free radical homopolymerizations of these monomers have been carried out in solution of ethanol/water (2.5/1:v/v), using 2,2 0-azo(2-methylpropionamidine) dihydrochloride (AMPAHC) as initiator. They lead to homopolymers in moderate to excellent yields. Structure of the polymers has been confirmed by SEC/ MALLS and 1 H-NMR spectra. The photopolymerization behavior of the synthesized monomers with N,N 0-diethyl-1,3-bis(acrylamido)propane has been investigated by DSC. New self-etch primers, based on these acrylamide monomers, have been formulated. Dentin shear bond strength measurements have shown that primers based on (N-methylacrylamido)alkylphosphonic acids assure a strong bond between the tooth substance and a dental composite. Moreover, the monomer with the longest spacer group provides the highest shear bond strength. V

Four new monomers, 3-(N-methylacrylamido)propylidenebisphosphonic acid, 3-(N-propyl-acrylamido)propylidenebisphosphonic acid, 3-(N-hexylacrylamido)propylidenebisphosphonic acid, and 3-(N-octylacrylamido)propylidenebisphosphonic acid, have been synthesized in good yields and fully characterized by 1 H, 13 C, 31 P NMR, and HRMS. The copolymerization of these monomers with N,N 0 -diethyl-1,3bis(acrylamido)propane (DEBAAP) has been investigated with differential scanning calorimetry. These mixtures show a higher reactivity than DEBAAP. New self-etch dental primers, based on these acrylamide monomers, have been formulated. Dentin shear bond strength measurements have shown that primers based on these bisphosphonic acids assure a strong bond between the tooth substance and a dental composite.

No abstract

Bis(4‐methoxybenzoyl)diethylgermane (BMDG) is used for the photopolymerization of six 1,1‐disubstituted 2‐vinylcyclopropanes (VCPs). A significantly higher photopolymerization reactivity compared to the conventional camphorquinone (CQ)/amine or CQ/amine/iodonium salt photoinitiator systems is observed. Furthermore, the influence of the electron‐withdrawing substituents on the monomer reactivity is investigated. 1‐Ethoxycarbonyl‐1‐ethylcarbamoyl‐2‐vinylcyclopropane 5 and 1‐ethoxycarbonyl‐2‐vinylcyclopropanecarboxylic acid 2 are found to be the most reactive monomers. 1,1‐Disubstituted VCP‐based dental composites containing BMDG are formulated. Those materials exhibit good mechanical properties as well as a low polymerization shrinkage.

No abstract

The combination of vinylcyclopropanes with an ester-activated vinyl sulfonate ester in a light-induced radical polymerization shows high reactivity accompanied by a significant increase in conversion and it leads to an enhanced reduction of polymerization-induced shrinkage stress.

No abstract

The regulation of multifunctional methacrylates to yield tough photopolymers is a widely researched topic, whereby addition−fragmentation chain transfer (AFCT) agents represent one viable class of additives. Vinyl ethers have been described as potent AFCT agents in radical polymerization but are unexamined in network formation via photopolymerization. In this article, we present a sterically hindered vinyl ether as AFCT agent for methacrylate networks, which shows enhanced acid stability opposed to vinyl ethers described in the literature. After synthesis and confirmation of the efficient regulation in a monofunctional system, the reactivity and mechanical properties in a difunctional methacrylate were evaluated. An increase in double bond conversion, significantly lower shrinkage stress, and high toughness were assessed and substantiated the great potential of this compound in photopolymerizable resins.