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A novel distorted lactam motif, namely 4,4′-dialkyl-[6,6′-bithieno[3,2-b]pyridine]-5,5′(4H,4′H)-dione (BTP), could lock itself by intramolecular hydrogen bonds. In view of the potential of the motif, two D–A conjugated polymers, PBDT-BTP-HD and PBDT-BTP-OD, with two different long side chains consisting of 4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene (BDT) as a donor unit and BTP as an acceptor unit were designed and synthesized. Furthermore, the photophysical, electrochemical and photovoltaic properties of both polymers were investigated. The morphologies and molecular ordering of the neat polymers and blend films were also probed to relate the side chain structures with aggregation states and device parameters. The device based on PBDT-BTP-OD with IT-M exhibited a power conversion efficiency of up to 9.54% thanks to the synergistic effect of the building blocks and side-chain engineering. As a result, it is successfully demonstrated that the novel distorted lactam BTP is a promising building block in organic solar cells.

Vitrimers instead of traditional materials is deemed as an effective way to solve the problem of material recycling. However, because of the reversible nature of dynamic covalent bonds, it is a challenge to improve the thermostability of vitrimers. Herein, we present a facile strategy by adding a small quantity of heterocyclic aramid to epoxidized natural rubber to simultaneously reinforce the mechanical properties and thermostability of dynamically cross-linked rubber. The improved comprehensive performances of vitrimer rubber resulted from the hydrogen bonds and covalent cross-linking bonds formed between epoxidized natural rubber and heterocyclic aramid fillers.

Biosynthetic residues in vulcanized natural rubber (VNR) create a blend end-linking network through two kinds of terminal groups dispersed in the covalent network, leading to excellent mechanical properties, such as high tensile strength and high crack growth resistance. However, due to the complex composition of natural rubber (NR), it is not likely to rebuild the terminal structures directly. In this circumstance, this work designs the terminal structures of synthetic polyisoprene by mimicking the structure of NR at the principal level. In detail, oligopeptide groups and phosphate groups were attached at the end of polyisoprene respectively, to form similar end-linking network as found in VNR. Three terminal functionalized model polymers containing oligopeptides (4A), phosphates (P) or both oligopeptides and phosphates (PA) were synthesized and vulcanized to generate V4A, VP and VPA, respectively. The oligopeptides and phosphates interact with each other to form new blended aggregates, which makes the end-linking network integrated. Blended aggregates are captured by the CLSM and TEM. The rheological tests demonstrate that the formation of blend aggregates is the foundation of synergistic effect on shear modulus, which will disappear at high temperature or solution state. It is also found that the mechanical properties of VPA are superior to that of VP and V4A, which is attributed to the more integrated end-linking network structure. Further analysis showed that the synergistic effect between terminals makes the entanglements near the blended aggregates difficult to unwrap and become permanent entanglements, thereby increasing the crosslinking density. The more complete end-linking network endow VPA higher crystallization ability than VP and V4A. These results expand our understanding of how terminals work in NR and provide new insight into the generic design of mechanically strong elastomer.

Two pairs of polymer donor materials based on indacenodithiophene (IDT) and indacenodithieno[3,2-b]thiophene (IDTT) as the donor units are synthesized. Thiophene or selenophene is introduced as the π-bridge units and electron-deficient fluorine-substituted quinoxaline is used as acceptor unit. Selenophene-containing polymers PIDT-DFQ-Se and PIDTT-DFQ-Se show redshifted absorption and narrower bandgaps. Combined with IDTT donor unit, PIDTT-DFQ-Se shows the highest absorption coefficient. Both the IDTT unit and selenophene unit have positive effects on the hole mobilities, making PIDTT-DFQ-Se the highest one. The best power conversion efficiency of 7.4% is obtained from devices based on PIDTT-DFQ-Se:[6,6]-phenyl C71 butyric acid methyl ester (PC71 BM) with a Jsc of 12.6 mA cm-2 , a Voc of 0.89 V, and a fill factor (FF) of 0.66.

Non-covalent interactions imposed by polar groups affect the properties of polyisoprene in various ways. But traditional modification method only led to randomly functionalized product which ignored the effects of sequence and location of polar groups. In this work, by using a novel polar monomer hydroxyl-myrcene (HMY), hydroxyl group terminally (BC–OH) and randomly functionalized (RC-OH) polyisoprene copolymers were successfully obtained. Due to the different hydroxyl group sequences, BC-OH and RC-OH shows different morphologies and rheological properties. Furthermore, polyhedral oligomeric silsesquioxanes (POSS) with urea bond was used as nanofiller to attach on BC-OH and RC-OH and generating BC-POSS and RC-POSS, respectively. The assembly of POSS and the formation of urea hydrogen bond will occur collaboratively. As a result, BC-POSS and RC-POSS showed distinct morphological properties and thermal stabilities. It is found that ordered urea bonds were formed in RC-POSS, while less ordered urea bonds were formed in BC-POSS. Overall, these results suggest that the tailoring of polar group sequence in polyisoprene copolymers could be a promising avenue for tuning polyisoprene performance via tuning aggregation behaviors of the polar groups.

Macrolide drugs, such as clarithromycin (CAM), are a key component of many combination therapies used to eradicateHelicobacter pylori. However, resistance to CAM is increasing inH. pyloriand is becoming a serious problem inH. pylorieradication therapy. CAM resistance inH. pyloriis mostly due to point mutations (A2142G/C, A2143G) in the peptidyltransferase-encoding region of the 23S rRNA gene. In this study an enzymic colorimetry-based DNA chip was developed to analyse single-nucleotide polymorphisms of the 23S rRNA gene to determine the prevalence of mutations in CAM-related resistance inH. pylori-positive patients. The results of the colorimetric DNA chip were confirmed by direct DNA sequencing. In 63 samples, the incidence of the A2143G mutation was 17.46 % (11/63). The results of the colorimetric DNA chip were concordant with DNA sequencing in 96.83 % of results (61/63). The colorimetric DNA chip could detect wild-type and mutant signals at every site, even at a DNA concentration of 1.53×102 copies μl−1. Thus, the colorimetric DNA chip is a reliable assay for rapid and accurate detection of mutations in the 23S rRNA gene ofH. pylorithat lead to CAM-related resistance, directly from gastric tissues.

To evaluate the safety and immunogenicity of split influenza vaccine (Anflu(®)).An open-labeled clinical trial was carried out in adults aged 18 - 60 years and elders aged over 60 years from August to September, 2010 in Shenyang, Liaoning province. One dose of split influenza vaccine was administered and adverse events were observed. Serum samples were obtained prior to vaccination and 21 days post vaccination. A/H1N1, A/H3N2 and B antibodies against influenza virus were measured using micro-hemagglutination inhibition (HI) assay.A total of 130 subjects were recruited and 120 paired serum samples were obtained. The overall rate of adverse events was 2.3% (3/130) and all of them with systemic reaction. No single serious adverse event was reported. 21 days after the vaccination, the sero-conversion rates of A/H1N1, A/H3N2 and B antibodies against influenza virus among adults were 82.5%, 93.7% and 92.1%, respectively. The Geometric Mean Titer (GMT) ratios were 20.2, 32.0 and 11.4, while the sero-protection rates were 92.1%, 98.4% and 98.4%, respectively. The sero-conversion rates of antibodies among elders were 89.5%, 91.2% and 87.7%, with the GMT ratios as 23.9, 39.8 and 15.1, respectively. The sero-protection rates were 93.0%, 94.7% and 96.5%, respectively.All indexes of A/H1N1, A/H3N2 and B antibodies exceeded the licensure criteria established by the EU Committee for Medicinal Products for Human Use, proving the trial vaccine Anflu(®) with good safety and immunogenicity.