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Summary: Karyotypes provide key cytogenetic information on the phylogenetic relationships and evolutionary origins in related eukaryotic species. Despite our knowledge of the chromosome numbers of sugarcane and its wild relatives, the chromosome composition and evolution among the species in the Saccharum complex have been elusive owing to the complex polyploidy and the large numbers of chromosomes of these species.Oligonucleotide‐based chromosome painting has become a powerful tool of cytogenetic studies especially for plant species with large numbers of chromosomes. We developed oligo‐based chromosome painting probes for all 10 chromosomes in Saccharum officinarum (2n = 8x = 80). The 10 painting probes generated robust fluorescence in situ hybridization signals in all plant species within the Saccharum complex, including species in the genera Saccharum, Miscanthus, Narenga and Erianthus.We conducted comparative chromosome analysis using the same set of probes among species from four different genera within the Saccharum complex. Excitingly, we discovered several novel cytotypes and chromosome rearrangements in these species.We discovered that fusion from two different chromosomes is a common type of chromosome rearrangement associated with the species in the Saccharum complex. Such fusion events changed the basic chromosome number and resulted in distinct allopolyploids in the Saccharum complex. [ABSTRACT FROM AUTHOR]

The direct ring‐opening polymerization (ROP) of propylene carbonate (PC) only affords oligomers with substantial unidentified by‐products, which hinders the efficient utilization of PC. Through detailed studies, for the first time, a careful mechanism involving the in situ release of propylene oxide (PO) from PC decarboxylation is proposed. Further, we report a novel strategy of copolymerization of PC/cyclic anhydrides via in situ capture of the formed intermediates. Results show that PC is successfully transformed into polyesters. Especially for the ring‐opening alternating copolymerization (ROAC) of PC/phthalic anhydride (PA), a variety of advantages are manifold: i) slow‐release of PO ensuring a perfectly alternating structure; ii) quantitative and fast transformation of PC; iii) visualization of polymerization process by a CO2 pressure gauge. Of importance, through tandem polymerizations, PC is fully transformed into polyesters and polycarbonates concurrently, thus achieving PC utilization with a high atom‐economy. [ABSTRACT FROM AUTHOR]

Site-specific functional polymers are generally synthesized from functionalized chain transfer agents (CTA) in the presence of catalysts. However, the poor solubility or chemical inertness of CTAs may make polymerizations uncontrollable. Now, this issue is addressed by proposing a strategy of designing chain-transfer-catalyst (CTC) that combines catalyst and CTA into one. The occurrence of catalytic effect naturally triggers the chain transfer process to give catalyst-labeled polymers with well-defined structures. As a proof-of-concept, cobalt(III) porphyrin catalysts with one, two and four hydroxyl groups act as efficient CTCs, giving the corresponding site-specific functional poly(propylene carbonate)s (PPC), diversifying the topology of polymers. Furthermore, porphyrin-capped PPCs with controllable Mn in the range of 1,000–16,800 g mol−1 were obtained by using monofunctional CTC (CTCOH). Moreover, different from traditional "catalyst+CTA" systems, a novel dynamic network transfer mechanism of CTCOH was proposed. This study provides a CTC strategy for the synthesis of site-specific functional polymers. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Thermoresponsive polymers with simultaneous biodegradability and signal "self‐reporting" outputs that meet for advanced applications are hard to obtain. To address this issue, we developed fluorescence signal "self‐reporting" biodegradable thermoresponsive polycarbonates through the immortal copolymerization of CO2 and oligoethylene glycol monomethyl ether‐functionalized epoxides in the presence of hydroxyl‐modified tetraphenylethylene (TPE‐OH). TPE‐OH was used as chain transfer agent to afford well‐defined polycarbonates with controlled molecular weight (6000—17000 g·mol–1) and aggregation‐induced emission characteristics. Through temperature‐dependent fluorescence intensity study, low critical solution transition of TPE‐labeled polycarbonates were determined and the fine details of thermal‐induced phase transition process were monitored. Further research indicated that temperature‐controlled aggregation and dissociation of TPE moieties are the main reason for fluorescence intensity variations. We anticipate that this work could offer a method to visualize the thermal transition process of thermoresponsive polycarbonates and broaden their application fields as smart materials. [ABSTRACT FROM AUTHOR]

This work focuses on two meaningful points in green chemistry, one is providing a practical solution for CO2 transformation into a CO2 copolymer, and the other is disclosing the potential application of a CO2 copolymer as a water dispersible binder to overcome the bottleneck in heavy metal free anti-corrosion coatings. For the first point, a CO2-copolymer like CO2-polyol is synthesized from the telomerization of CO2 and propylene oxide using a zinc–cobalt double metal cyanide complex as a catalyst and terephthalic acid as a chain transfer agent. For the second point, for the past 30 years conducting polyaniline, with its unique anti-corrosion behaviour, has been regarded as a heavy metal free anti-corrosion material, but the development of a waterborne polyaniline anti-corrosion coating has encountered an impasse owing to the lack of a compatible binder. Therefore, a water borne cationic polyurethane dispersion (CPUD) was developed for this purpose, in which CO2-polyol was used as a soft segment, and 1,4-butanediol di(3-diethylamino-2-hydroxypropyl alcohol) ether was synthesized as a side-chain cationic extender. Unlike earlier acidic water borne dispersions, this water borne CPUD was near neutral, ensuring good compatibility with an aqueous conducting polyaniline dispersion, and is expected to create significant possibilities for the development of a novel generation of sustainable and eco-friendly metal anti-corrosion materials. [ABSTRACT FROM AUTHOR]