4350-83-8Relevant articles and documents
Hybrid monomer design for unifying conflicting polymerizability, recyclability, and performance properties
Caporaso, Lucia,Cavallo, Luigi,Chen, Eugene Y.-X.,Falivene, Laura,Li, Zi-Chen,Shi, Changxia
, p. 670 - 685 (2021)
Synthetic polymers have become indispensable for modern life and the global economy. However, the manufacturing and disposal of most of today's polymers follow a linear economy model, which has caused accelerated depletion of finite natural resources, severe worldwide plastics pollution, and enormous materials value loss. The design of future circular polymers considers closed-loop lifecycles toward a circular economy. A key challenge of this promising design includes innovation in monomer structure that could enable not only efficient polymerization to polymers with properties comparable to today's polymers but also selective depolymerization to recover the monomers with high yield and purity. However, these contrasting properties are conflicting in a single monomer structure. This work introduces a hybrid monomer design concept that hybridizes contrasting parent monomer structures to an offspring monomer that can unify conflicting (de)polymerizability and performance properties. Intrinsically recyclable polymers represent a circular economy approach to address plastics problems. However, the design of such circular polymers is challenged by unyielding trade-offs between the monomer's polymerizability and the polymer's depolymerizability and performance properties. Here, we introduce a hybrid monomer design strategy that synergistically couples a high ceiling temperature (HCT) sub-structure for high polymerizability and performance properties with a low ceiling temperature (LCT) sub-structure for high depolymerizability and recyclability within the same monomer structure. Thus, structural hybridization between HCT ε-caprolactone and LCT γ-butyrolactone led to an offspring [3.2.1]bicyclic lactone, which exhibits both high polymerizability and depolymerizability, otherwise conflicting properties in a typical monomer. The resulting polymer becomes a high-performance material, and thermal transition temperatures are ～200°C higher and tensile modulus 10× higher than its parent polymers. These results demonstrate that the HCT/LCT hybrid monomer strategy is a powerful approach for designing circular polymers where conflicting properties must be exploited and unified. Hybrid monomer design is shown to be a powerful approach to develop robust circular plastics without yielding to common property trade-offs by hybridizing parent monomer structures to an offspring monomer that can unify conflicting (de)polymerizability and performance properties.
RECYCLABLE POLYMERS BASED ON RING-FUSED GAMMA-BUTYROLACTONES
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Page/Page column 34; 44; 48, (2020/02/23)
The invention discloses a class of new polymers, trans-ring-fused poly(4-hydroxybutyrate)s (RF-P4HB) that exhibit a unique set of properties, including robust thermal stability and mechanical strength, quantitative recyclability to the building block monomers via thermolysis and/or chemical catalysis, and convenient production from the chemical ring-opening polymerization under ambient temperature and pressure. Another unique property is the formation of crystalline stereocomplexed polymers with high melting temperature upon mixing the two enantiomeric RF-P4HB chains via stereocomplexing co-crystallization. This invention also provides the corresponding ring-fused lactone monomer structures that enable the synthesis of the RF-P4HB polymers, through trans-fusing of rings to the parent γ-butyrolactone ring. Furthermore, a polymerization or copolymerization process for the synthesis of RF-P4HB polymers and copolymers is disclosed.
1- (1-CYCLOHEXYL-4-PIPERIDINYL) -1, 3-DIHYDRO-2H-BENZIMIDAZOL-2-ONE DERIVATIVES WHICH HAVE ACTIVITY ON THE M1 RECEPTOR AND THEIR USE IN MEDICINE
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Page/Page column 49-50, (2008/12/04)
Compounds of formula (I) or a salt thereof are provided, wherein R4, R5, R6, Q and R are as defined in the description. Uses of the compounds as medicaments and in the manufacture of medicaments for treating psychotic disorders and cognitive impairments are disclosed. The invention further discloses pharmaceutical compositions comprising the compounds.
