XPush-pull indole-containing nonlinear optical chromophores with different acceptor and ð-conjugated moieties have been synthesized and characterized. Experimental measurements of the second-order nonlinear optical response demonstrated that the chromophores exhibit similar or superior optical nonlinearity compared with their analogues with an aniline moiety as the donor group, but the indole-based chromophores display blueshifted absorption, even up to 30 nm.

Two series of polyurethanes (P1-P10) containing NLO chromophores as side chains were prepared, in which the size of isolation groups was changed from small atoms to much larger groups such as carbazolyl groups. The polymers were well characterized. The tested NLO properties of the polymers demonstrate that the NLO values and the poling efficiency of the polymers are not always improved with increasing of the size of isolation spacer, and for a given chromophore moiety, there is a suitable isolation group present to boost its microscopic â value to possibly higher macroscopic NLO property efficiently.

For the first time, a conjugated fluorescent polymer was utilized to probe R-amino acids, sensitively and selectively, through a new approach. First the strong fluorescence of the prepared polyfluorene (P1) was quenched by trace copper ions, and then the quenched fluorescence was recovered upon the addition of R-amino acids, making P1 a new and sensitive biosensor toward R-amino acids. The experimental results demonstrated that the R-amino acid selective nature of P1 over other analytes was relatively good. Thus, the work reported here might open up a new avenue for developing new biosensors.

For the first time, a series of dendronlike main-chain polyurethanes have been successfully designed and synthesized, in which different isolation groups with different sizes were introduced to modify the subtle structure of the used "H"-type chromophores, according the concept of "suitable isolation groups". Thanks to the advantages of "H"-type chromophores and the introduced suitable isolation group, all of the polymers demonstrated large NLO effects, good processability, improved optical transparency, and thermal stability. The obtained experimental results indicated that the utilization of "H"-type chromophores might be a promising choice to efficiently translate the large-values of the organic chromophores into high macroscopic NLO activities of polymers.