A Novel One-Pot Synthesis of Poly(Propylene Carbonate) Containing Cross-Linked Networks by Copolymerization of Carbon Dioxide, Propylene Oxide, Maleic Anhydride, and Furfuryl Glycidyl Ether

Abstract

The thermoplastic poly(propylene carbonate) (PPC) containing cross-linked networks was one-pot synthesized by copolymerization of carbon dioxide, propylene oxide (PO), maleic anhydride (MA), and furfuryl glycidyl ether (FGE). The copolymers were characterized by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) measurements. The thermal and dimensional stability of the copolymers were improved. When the MA and FGE load increased from 1 mol% to 4 mol% of PO, the copolymers contained the gel contents of 11.0%–26.1% and their yields were about double that of the PPC. The 5% weight-loss degradation temperatures (Td,-5%) and the maximum weight-loss degradation temperatures (Td,max) increased from 149.7–271.3 °C and from 282.6–288.6 °C, respectively, corresponding to 217.1 °C and 239.0 °C of PPC. Additionally, the hot-set elongation tests showed that the copolymers exhibited elasticity and dimensional stability with the minimum permanent deformation of 6.5% which was far less than that of PPC of 157.2%, while the tensile strengths were a little lower than that of PPC because of the following two conflicting factors, cross-links and flexibility of the units formed by the introduced third monomers, MA and FGE. In brief, we provide a novel method of one-pot synthesis of PPC containing cross-linked networks. According to this idea, the properties would be more extensively regulated by changing the cross-linkable monomers.

Enhanced Poly(propylene carbonate) with Thermoplastic Networks: A Cross-Linking Role of Maleic Anhydride Oligomer in CO2/PO Copolymerization

“…This significant improvement in thermal stability is attributed to the formation of cross-links in the PPC matrix by introducing MAO into PPC chains, even with minimal MAO feed (0.625 wt % of PO), since the cross-linking significantly limits the unzipping reaction. Combining our previous studies on the preparation of cross-linked PPC by terpolymerization of multifunctional third monomers with CO 2 and PO [30,31,32,34], we find that adding a small amount of multifunctional third monomer can significantly increase the thermal decomposition temperature without exception. Suppressing the unzipping degradation plays a key role.…”

“…The number molecular weight ( M n ) of MAO is 540 g·mol −1 with polymer dispersity index of 1.03, which was determined by gel permeation chromatography (GPC) (Figure S1). Zinc glutarate (ZnGA) catalyst was synthesized according to literature [34]. High pure nitrogen gas was purchased from Zhanjiang Oxygen Plant (Zhanjiang, China).…”

“…Different from the above two-step methods, which are to first prepare PPC followed by cross-linking, the third method is to directly get cross-linked PPC by one-step terpolymerization of CO 2 , PO, and a multifunctional third monomer that usually contains epoxide, anhydride, or isocyanate group, such as vinylcyclohexene dioxide [27], 1,2,7,8-diepoxyoctane, 1,2,9,10-diepoxydecane [28], diphenylmethane diisocyanate [29], pyromellitic dianhydride [30], triglycidyl isocyanurate [31], and bicyclo(2,2,2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride [32] itaconic anhydride [33]. Our group also prepared PPC with networks in one pot by introducing functional groups, which can react with each other, into the PPC pendants through multi-copolymerization of CO 2 , PO, MA, and furfuryl glycidyl ether [34]. It should be noted that, sometimes, some types of multifunctional third monomers, such as diepoxide [35,36] and polyisocyanate [37], cannot form cross-linking structure by copolymerizing them with PO and CO 2 .…”

Cross-Linked Networks in Poly(propylene carbonate) by Incorporating (Maleic Anhydride/cis-1,2,3,6-Tetrahydrophthalic Anhydride) Oligomer in CO2/Propylene Oxide Copolymerization: Improving and Tailoring Thermal, Mechanical, and Dimensional Properties

“… 28 Itaconic anhydride that contains both C=C bond and cyclic anhydride was also used as a third monomer to prepare cross-linked PPC. 39 In addition, our group prepared PPC with networks by CO 2 /PO/MA/furfuryl glycidyl ether copolymerization, 40 in which the functional groups that can react with each other were introduced into the PPC pendants.…”

“…If the third monomer is too flexible, the tensile strength would be significantly reduced, even the cross-linked networks are contained. 40 However, it is difficult to further verify the above finding because there are not many multifunctional small molecules, commercially, that can participate in CO 2 /PO copolymerization, and their custom synthesis is not economical. We have tried to use a maleic anhydride oligomer as the third monomer to prepare cross-linked PPC.…”