anionic form under the alkylation conditions. This same trend was observed for the alkylation of pyrido [2,3,4,5-lmn ]phenanthridine under basic conditions. [ 24 ] Owing to the different functional groups, M1 and M2 can be easily separated on a chromatographic column or purifi ed by recrystallization. To obtain low band gap and processable materials, these monomers were copolymerized with 2,5-bis(2-octyldodecyl)-3,6-di(thien-2-yl)pyrrolo [3,4-c ]pyrrole-1,4-dione ( M3 ) (see the Supporting Information). [ 25 ] The polymerization reactions are also described in Scheme 1 . Two alternating copolymers ( P1 and P2 ) and one random terpolymer ( P3 ) were synthesized via simple direct (hetero)arylation polymerization (DHAP) (see the Supporting Information), a "greener" method which has rapidly developed in recent years. [26][27][28] The advantages of DHAP are manifold, and include a reduction in the number of reaction steps and the elimination of toxic organometallic by-products. The polymerization conditions utilized here are based on a recent report which has shown a high selectivity between aryl-bromide and non-substituted thiophene units. [ 29 ] Suzuki cross-coupling polymerization reactions were also performed for comparison purposes (see the Supporting Information). All polymers are soluble in common chlorinated solvents, such as chloroform (CF) and o -dichlorobenzene (ODCB), as well as chlorine-free solvents such as o -xylene. Interestingly, it has been noted that P2 ( M n = 60 kDa, PDI = 4.0) always afforded higher molecular weights than P1 ( M n = 43 kDa, PDI = 4.0). This could be explained by the greater solubility of P2 . Finally, a terpolymer P3 was obtained by copolymerizing the resulting 35:65 mixture of M1 and M2 with one equivalent of M3 . With a high ratio (65%) of monomer M2 into the structure of the random terpolymer P3 , this polymer ( M n = 57 kDa, PDI = 2.9) displays a good solubility in common solvents. The electrochemical properties of the polymers were investigated by cyclic voltammetry (CV) and are reported in Figure 1 b and Table S1 (Supporting Information). The occupied and unoccupied molecular orbital (HOMO/ LUMO) levels of P1 , P2 , and P3 are −5.48/−3.93, −5.46/−3.95, and −5.43/−3.92 eV, respectively, which indicate good stability in air and similar electronic properties between polymers. As reported in Figure 1 , the pristine green polymers ( P1 , P2 , and P3 ) exhibit broad UV-vis absorption spectra with an optical band gap ( E g opt ) of 1.64-1.65 eV, which is in agreement with the measured electrochemical band gap ( E g elect = 1.51-1.55 eV). Thermogravimetric analyses revealed that all polymers are stable up to 400 °C ( Figure S11, Supporting Information). Also, differential scanning calorimetry (DSC) measurements indicate that all these non-symmetric polymers are amorphous, as no glass transition temperature is observed between 25 and 250 °C. The DSC results are corroborated by X-ray diffraction (XRD) measurements (see the Supporting Information).Organic solar cells (OSC) have attrac...
Background Studies have reported unmet health needs in individuals with intellectual disability (ID). This study illustrated and analysed patterns of healthcare services utilization among people with intellectual disability and compared their use to that of the general population. Method Participants (N = 791, aged 15–82) were mainly recruited through government‐financed agencies specializing in services for people with intellectual disabilities in Québec, Canada. Comparisons were possible by using health administrative data. Results Some services were more used by people with intellectual disability than the general population (general medicine, psychiatry, PSA blood tests), and others were accessed at significantly lower frequencies (optometry, physiotherapy, Pap tests). Similar rates were found for mammography, dentistry and psychology. Inequities were more salient for individuals who had more severe levels of intellectual disability. Conclusions Our findings support that the population with intellectual disability would benefit from policies and practices aimed at enhancing the access to healthcare services.
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