Journal of Polymer Science最新文献

A ferrocene-containing oligoorganosiloxane with a number-average degree of polymerization of 8.8 and a number-average molecular weight of 3200 is synthesized by hydrolytic condensation of 3-aminopropyltriethoxysilane followed by chemical modification of the resulting oligomer with acetylferrocene. Its structure is characterized by MALDI-TOF, NMR and IR spectroscopy. ¹H NMR spectroscopy shows the predominance of more thermodynamically stable units containing anti-configuration Schiff bases. Using IR spectroscopy as well as experimental determination of surface energy and its polar (acid–base) and dispersion components, the covalent immobilization of ferrocene-containing oligoorganosiloxane on a glass surface after heating at 110°C is shown. The formed coating provides hydrophobization, acid–base indifference of the glass surface and serves as a precursor for the formation of magnetically soft materials after pyrolysis in argon already at 350°C. The main stages of ferrocene-containing oligoorganosiloxane thermal destruction in an inert atmosphere and the formation of a mixture of iron and silicon oxides during its thermal oxidative destruction are established by combination of TGA/DTA, IR spectroscopy and elemental analysis. The proposed approach opens up new possibilities for functionalizing silicates surfaces, creating magnetic glasses, as well as regulating surface energy and its components.

Shape memory polymers (SMPs) are novel kinds of smart materials whose shape can be changed in external conditions such as heat stimulus. Due to their excellent structural versatility and high elastic strain, they have important applications in the field of biomaterials. Here, a series of amorphous shape memory polymer materials are prepared and their shape memory properties and glass transition temperature (T _g) are also investigated. A special kind of epoxy polymer, whose shape can be changed at around physiological temperature, is synthesized by regulating the crosslinking density and introducing flexible aliphatic epoxy chains. The shape memory function of this epoxy polymer is studied by deformation test. In addition, to explore their application in the field of biomedical materials, the biocompatibility of the materials are evaluated, including the effects on the erythrocyte hemolysis rate and cell activity. The experimental results show that this kind of epoxy polymer has good shape memory function and biocompatibility.

In this paper, two synthetic routes for non-isocyanate carbamate acrylates (CAs) were explored. Four amino alcohols reacted with ethylene carbonate respectively forming carbamate alcohols. Additionally, carbamate amines were synthesized through the reaction of diethylene glycol with dimethyl carbonate, followed by the reaction of 4-methylcyclohexane-1,3-diamine. Five kinds of CAs were synthesized via oxa-Michael addition of carbamate alcohols and aza-Michael reactions of carbamate amines with neopentyl glycol diacrylate (NPGDA), respectively. The resulting intermediates and final CAs were characterized by electrospray ionization high-resolution mass spectrometry (ESI-HRMS), ¹H NMR, and FT-IR spectroscopy. The photopolymerization kinetics of the CAs were investigated using FT-IR spectroscopy. Under UV irradiation and initiation by 1 wt% 2-isopropylthioxanthone (ITX) for 30 s, the double bond conversion of the CAs synthesized by oxa-Michael addition were over 95%. The resulting CAs can be UV cured to form a transparent film with a gel content of 90%–95%, a hardness of 4–5 H, and a flexibility of 1 mm. A formulation consisting of 79 wt% CA2, 20 wt% NPGDA, and 1 wt% ITX was applied for 3D printing to produce various models with smooth surfaces, high precision, and excellent flexibility.

The growing demand for lipid–polymer conjugates (LPCs) in biomedicine highlights the need for efficient synthesis methods. This study presents a novel Y-type photoiniferter reagent (Lipid-PIT) with a diethyldithiocarbamate group and a diacylglycerol group. Lipid-PIT efficiently initiated the polymerization of vinyl monomers such as oligo(ethylene glycol) methacrylate (OEGMA), N,N-dimethylacrylamide (DMA), tert-butyl acrylate (tBA), and n-butyl acrylate (nBA) under UV irradiation at room temperature, yielding LPCs. Proton NMR confirmed the presence of diethyldithiocarbamate and diacylglycerol moieties at the chain ends. The polymerization kinetics of DMA showed a linear increase in molecular weight (M _n) with time, with a polydispersity (Đ) below 1.50, demonstrating high controllability. Moreover, Lipid-PIT allows for the creation of block copolymers via secondary chain extension. In vitro assays revealed that LPCs synthesized from OEGMA monomers successfully modified L929 and HeLa cell surfaces and exhibited good biocompatibility. This study offers a rapid, efficient method for LPC synthesis with promising biomedical applications.

CO₂-based polycarbonate diols (PPCDLs) are important raw materials. PPCDLs with high carbonate linkage (up to 99%) were controllably synthesized in high efficiency from CO₂ and propylene oxide (PO) by synchronously using tetrabutyl ammonium salt of succinic (ASA) as a difunctional initiator and 1,4-butanediol (BDO) as a difunctional proton exchange agent (PEA) in the presence of triethyl borane (TEB). In this system, the difunctional initiator (ASA) with two carboxylic anions accelerates the polymer chain propagation process, and the difunctional PEA with two active protons facilitates the proton exchange process. The molecular weight and production efficiency of PPCDL can be finely tailored by varying the feed molar ratios of PO to ASA, TEB, and BDO. Upon optimizing this scalable process, the PPCDLs with molecular weights between 1000 and 3000 Da are produced in high yields with a reaction time of 8–12 h, which is much faster than the monofunctional initiator in the presence of BDO (typically 20–36 h) or consumes much less amount of TEB and initiator in the absence of BDO. The synthesized PPCDLs possess a high 1^oOH content of the terminal hydroxyl groups and a high carbonate content. Thermoplastic poly(carbonate urethane)s (PCUs) are synthesized by copolymerization of the title PPCDLs, 4,4′-dicyclichexylmethane diisocyanate (HMDI) and BDO. Due to their high transparency and excellent mechanical properties, PCUs have great potential in the polyurethane industry, such as coatings, adhesives, leather, and thermoplastics.

Self-healing polymeric gels have emerged as a promising class of materials due to their ability to repair damage autonomously, offering significant advantages for various applications. Nevertheless, a major hurdle to their widespread practical use lies in their often-compromised mechanical strength and long reaction time. Herein, we present the synthesis of a new type of self-healing hydrogels using poly(itaconic acid-co-hydroxypropyl alcohol-co-acrylic acid), also known as poly(IA-co-HPA-co-AAc), by a frontal polymerization (FP) method. The rapid reaction rate of FP facilitates the swift and energy-efficient synthesis of the hydrogels within 10 min, eliminating the need for prolonged reaction times. Additionally, the results revealed that the synthesized hydrogels exhibited pH-dependent responsiveness, robust mechanical integrity, and autonomous self-healing capabilities, obviating the requirement for external stimuli. The exceptional self-healing properties can be attributed to the extensive hydrogen bonding network between the polymer chains, enabling them to recover up to 80% of their original mechanical strength. Rheological analysis confirmed the presence of a robust and stable gel network, evidenced by high storage modulus (G′) values across the entire frequency and strain sweep tests. This research addresses a significant knowledge gap in IA-based hydrogels by introducing a rapid, optimized method for constructing self-healing materials through hydrogen bonding interactions.