Enhanced Poly(Propylene Carbonate) with Thermoplastic Networks: A One-Pot Synthesis from Carbon Dioxide, Propylene Oxide, and a Carboxylic Dianhydride

Abstract

Thermally and mechanically enhanced poly(propylene carbonate) (PPC) with networks was prepared by adding a cyclic carboxylic dianhydride, bicyclo(2,2,2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTCDA), in the CO2/propylene oxide (PO) copolymerization. The obtained copolymers were characterized by FT-IR, 1H NMR, DSC, and TGA. The gel, melt flow rate, hot-set elongation, and tensile properties were also measured. The formation of networks was confirmed by the presence of gel and the shape recovery after the hot-set elongation test. The minimum permanent deformation of the copolymer is 3.8% and that of PPC is 4539% higher than this value. The results show that BTCDA units are inserted into the backbone of PPC, and the PPC chains are connected successfully owing to cyclic multifunctional anhydride groups in BTCDA. With increasing feed molar ratio of BTCDA to PO from 1 to 4%, the yield strength of copolymers increases from 18.1 to 37.4 MPa compared to 12.9 MPa of PPC. The 5% weight-loss degradation temperatures and maximum weight-loss degradation temperatures greatly increase up to 276.4 and 294.7 °C, respectively, which are 58.6 °C and 55.1 °C higher than those of PPC. These enhanced properties originate from the formation of crosslinks by the rigid and bulky multifunctional dianhydride.

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

“…In fact, the yields of copolymers are 2–3 times that of PPC ( Table 1 ). In combination with previous studies on the CO 2 /PO/third monomer copolymerization catalyzed by ZnGA, 27 , 28 , 52 , 53 it is shown that the polymer yield increased when the third monomer was cyclic anhydrides but decreased when it was epoxides, when compared with the CO 2 /PO copolymerization. This related to the higher activity of cyclic anhydrides/PO copolymerization than epoxides/CO 2 .…”

“…The multifunctional monomer always contains several epoxides, isocyanates, or cyclic carboxylic anhydrides, such as vinylcyclohexene dioxide, 35 diphenylmethane diisocyanate, 36 1,2,7,8-diepoxyoctane, 37 1,2,9,10-diepoxydecane, 37 pyromellitic dianhydride, 27 triglycidyl isocyanurate, 38 and bicyclo(2,2,2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride. 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.…”

“…Our group has used several multifunctional third comonomers to prepare PPC with cross-linked networks. 27 , 28 It is found that adding a small amount of third monomers can improve the thermal and mechanical properties. In particular, for elevating the thermal decomposition temperature, the required amount of third monomers is smaller.…”

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

“…Organic silylated PPC following hydrolysis reaction can also form cross-linked PPC [32,33]. Compared with the two-step method, PPC can be obtained directly by one-step terpolymerization of PO and CO 2 with diepoxides [15,34], dianhydrides [35,36], or mixed monomers [37]. Sometimes, the addition of diepoxides in the CO 2 /PO copolymerization does not form cross-linked PPC [38,39], which may be related to the reactivity of the diepoxides.…”

Kinetic Model of Maleic Anhydride Grafting onto Poly(Propylene Carbonate) during Melt Compounding

“…Due to its low decomposition temperature, it is commonly used as a binder for tape casting processes and abrasive substrates production . While its low temperature and clean decomposition is advantageous from a burn off stand point, it limits its practical usage as a bulk product, along with the fact that it is an amorphous polymer with T g close to room temperature . For this reason, there have been many efforts to modify PPC through compounding with other bio‐ and petroleum‐based resins such as poly(lactic acid) (PLA), poly(butylene succinate) (PBS), polycaprolactone, polyoxymethylene, ethylene‐vinyl‐alcohol, and poly(vinyl alcohol), and fillers likes wood flour, natural fibers, and calcium carbonate .…”