Copolymers of Functionalized and Nonfunctionalized Polydicyclopentadiene

Abstract

Polydicyclopentadiene (PDCPD) is a thermoset polymer that is valued in industry for its excellent mechanical properties, heat resistance, and chemical tolerance. However, the commercial polymer lacks chemically tunable functionality. Recently, a methyl ester functionalized polydicyclopentadiene (f PDCPD) was shown to offer significantly improved tunability while maintaining the same thermal stability as the unfunctionalized parent polymer. In this report, we describe the synthesis and characterization of poly[(methyl ester functionalized dicyclopentadiene)-stat-(dicyclopentadiene)] copolymers in which the mole fraction of the functionalized, ester-containing monomer, relative to the unfunctionalized dicyclopentadiene monomer, is systematically increased. Our data reveal an ability to tune physical and mechanical properties of the copolymers (e.g., alpha transition and hardness) by changing the monomer ratio and thermal curing time. Importantly, the copolymers retain the same thermal stability as the individual homopolymers, while allowing for increased control over surface energy.

Synthesis and properties of cyclic olefin polymers by ring-opening metathesis (co)polymerization of α-methyl-substituted norbornene lactones

“…The polymer should be amorphous, with high glass transition (T g ) temperatures ranging from 120 °C to 170 °C but with possible deformation processing for optical transparency material application. ROMP has an advantage over coordination polymerization in the applicability to various NB monomers; however, to synthesize high T g polymers, polycyclic NB monomers, such as dicyclopentadienes, [5][6][7][8][9] tetracyclododecenes, [10][11][12] and others, [13][14][15][16][17][18][19] should be employed. Optical properties, including refractive indexes and birefringence, are also important factors.…”

A Single-Atom Upgrade to Polydicyclopentadiene

“…In part, this is likely due to the known surface oxidation of polydicyclopentadiene materials, which presumably raises the surface energy of all samples tested here, but possibly not at an equivalent rate. Additionally, packing effects may result in the localized concentration of ketone functional groups within 4 p,c being different at the surface than within the bulk …”

“…Additionally, packing effects may result in the localized concentration of ketone functional groups within 4 p,c being different at the surface than within the bulk. 20 To probe deeper into the polarity differences of the bulk materials, therefore, we conducted swelling experiments upon PCPD and oxaPDCPD samples, using both a polar and nonpolar solvent (methanol and toluene, respectively). As illustrated in Figure 3, we observed a dramatic difference between the two polymer materials.…”

“…Our lab took a different approach, adding a functional group (a C -linked methyl ester) through a strong sp 2 –sp 2 linkage at the less-strained alkene of the monomer ( 3 m , Figure ). − This yielded a polymer product ( 3 p and 3 p,c ) with superior properties, in which the T g , storage modulus, and thermal stability were all broadly equivalent to those of the parent PDCPD, but where the surface energy could be readily tuned (or even patterned) through surface saponification − and where dyes or drug molecules could be attached through esterification or amidation protocols . Unfortunately, while 3 p,c (which could be readily manufactured through reaction injection molding, akin to PDCPD itself) had many desirable features, the requisite ester-containing monomer was somewhat challenging to synthesize on a >100 g scale because its production through the partially selective Diels–Alder reaction of cyclopentadiene and carboxylated cyclopentadiene necessarily led to a mixture of regioisomers, only one of which was a substrate for metathesis polymerization.…”

High‐Performance Low‐k Poly(dicyclopentadiene) Nanocomposites as Achieved via Reactive Blending with Norbornene‐Functionalized Larger POSS

“…[12,13] Nevertheless, its further application is restricted by the modest glass transition temperature (T g ≈ 130 °C), high coefficient of thermal expansion (CTE, up to 140 ppm °C−1 ), and relatively high k value. [14][15][16] Although the functionalization of DCPD monomers, [16,17] regulation of the catalyst loading, [18,19] and addition of norbornene-based cross-linkable co-monomers [14,20] have been shown to enhance the thermal and mechanical properties of PDCPD, the higher polarization of these monomers and comonomers, along with higher catalyst loading are usually unfavorable to improve the dielectric properties. In general, both decreasing the molecular polarization and introducing air pores (k air ≈ 1) are effective strategies for reducing material's k value.…”