PowerPoint Presentation

Highly ordered alignment of a vinyl polymer by host-guest cross-polymerization

Kazuya Tomita

Regrettable present situationTo obtain crystallinity in polymer, you need some engineerings CatalystSpecifically designed polymerizationMechanical rubbing Microstructure-specific bindingThe use of supramolecular aligner molecules

However, you strongly desire other simpler and more general way, dont you?

Traditional common-sense in polymer chemistryCrosslinking gives AMORPHOUS materials (with thermal and solvent stability) Alignment gives CRYSTALLINE polymers (which has higher density)If introducing both crosslinking and alignment within one material, it could utilize both strengths.

amorphouscrystal

crosslinking

Making a scaffold for polymerization crosslinker

Monomer

MOF[Cu(terephthalate)triethylenediamine)] Crosslinkable MOF(1x)

Host-guest cross polymerization This polymer from above method fusions alignment and crosslinking This methodology is applicable to other polymers

Is it true that cross-polymerization occurred?

2-D 1H-13C PMLG HETCOR NMR spectra2ms8ms A direct demonstration that the crosslinker groups are co-polymerized with St,resulting in a unitary structure.

Is it true that cross-polymerization occurred?

Left SEM images provide evidence that the polymer objects form shape replica of the pristine MOF microcrystals.

Ordered alignment of PSt chains

X ray powder diffractgramsWithout the crosslinker, the polymer becomes amorphousAt a certain rate of the crosslinker, it becomes the most crystalline.

HR-TEMRegular PSt interchain spacing4.9Direct visualization

FFT of the HR-TEM imageEstimated structureDirect visualization

Other remarkable propertyRather higher density(1.13 g cm3)Unconventional thermal degradation behaviorStability even under extreme conditionSolvent stabilityCf) conventional PSt : 1.04 1.07 g cm3 ideal 100 % crystalline isotactic PSt : 1.125 g cm3After treating at 500 , the diffraction peak still exists.Although a high crosslinking density(40 mol%) is required to obtain a relavant char generation(40wt%),in cross-polymerized polymer, with 7 mol% you can obtain 45 wt% of char.

Insoluble in chloroform, acetone and dioxane

summaryHost-guest cross-linked polymerization is a extremely innovative method which enables us to make new type of materials which has alignment and crystallinity in one material. The new material from host-guest cross-linked polymerization has amazing properties such as themal and solvent durability likely to be used to many applications.