Speaker: Dr. Lu, Chu-HuaChang’s Lab10/26/2009

Reference: Ring-Opening Polymerization Mechanisms,

Catalysts, Structure, Utility (1993), edited by Daniel J. Brunelle

RING OPENING POLYMERIZATION- A SMART WAY TO IMPROVE CONDENSATION

POLYMERIZATION

1

OutlineROP: ring opening polymerizationImportance of ROPNylon (polyamide) (Cyclic amide monomers)Character of ROPMonomer 1: OxiraneMonomer 2: AcetalMonomer 3: Cyclic esterMonomer 4: phosphazenesMonomer 5: siloxaneSummary

2Conventional Radical Polymerization

Importance of ROP

3

conversion0% 100%M n

Living Radical Polymerization and ring-opening polymerization

Condensation Polymerization

High Mn high

viscosity and low

solubilityLow Mn

low mechanical properties and easy leaching

Conventional Radical Polymerization

High Mw/Mn for condensation polymerization

Importance of ROP

4

Condensation Polymerization of Nylon 6, 6

ROP of Nylon 6

Nylon 66 BedPictures from wikipedia.org

Nylon 66 BagNylon 6 Yard

Nylon (Polyamide)

5

Nylon ( 尼龍 ) 與其他熱可塑性塑膠相比，在強度、延展性、耐磨性及耐熱性上提供了卓越的平衡，並有很好的流動性及寬廣的加工成型範圍，使其成為最普遍被使用的工程塑膠之一。目前市場上有多種商品化 Nylon 材料可供選擇，如 : Nylon 6/6 、 Nylon 6 、 Nylon 6/10 、 Nylon 6/12 、 Nylon11 、 Nylon 12 、非結晶性 Nylon 及耐衝擊改質 Nylon 6/6… 等。

在各種商品化 Nylon 中， Nylon 6 具有堅韌、耐摩擦的特性，使其成為是最普遍使用的 Nylon 之一。與 Nylon 6/6 相比，其成型品外觀、耐潛變性及加工成型性均更加優異 ( Nylon 6 之溫度成型比 Nylon 6/6 大約低 27℃) ，此情況使其有較低的模收縮率 ) ，但相對的 Nylon 6/6 比 Nylon 6 有較低的模數，且吸濕速度較 Nylon 6/6 快 。與其他熱可塑性塑膠相比， Nylon 6 會從空氣中吸收較多的濕氣， 此現象對可加工性、尺寸穩定性和物理特性造成影響。對 Nylon 6 而言，吸收濕氣會提升其延伸率及韌性但相對會使其抗拉強度和剛性降低。 www.asiateck.com.tw

Characteristics of ROP

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Using cyclic monomersUsing “ionic” imitator Polymerization: transformation from intra-

chain bonds to inter-chain bonds and enthalpy from the ring strain of cyclic monomers.

Polymerization without releasing small molecules (cf. condensation polymerization).

Polymerization with low activation energy (cf. covalent bond for condensation polymerization).

Some cyclic monomers are prepared by chemical modification of α , ω –difunctional monomers for condensation polymerization.

Living polymerization (pseudo ionic polymerization): controllable and high molecular-mass polymers (cf. condensation polymerization (equivalent feeding ratios)).

[ R Z ]nn RZ

R: alkyl chain; Z: O, S, N, P, Si, or -CONH-，-COO- ， -CH=CH-, and so on.

Monomers, Catalysts and Polymerization

7 continued

Monomers, Catalysts and Polymerization

8

Monomers 1

9

Oxirane: O-cyclic monomers & using alcohol initiatorCH2 CH2

OCH2 CH CH3

OCH2Cl

CCH2

CH2

OCH2Cl

CH2

CH2

CH2

O

EOPEO POPPOCH2 CH2

CH2 CH2

O

CH2 CH2

CH2 CH2

CH2

CH2O

CH2

CH2 CH2

CH2

CH2

OCH2

CH2THFPTHFPU 的軟鏈段組成

( 保溼化粧品主要成份 )

PEO (PEG) Application

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Spenco 2nd Skin is a hydrogel sheet, consisting of cross-linked polyethylene oxide, and containing 96% water, supported upon a net of low density polyethylene, which provides strength. The gel, which is capable of absorbing approximately its own weight of wound exudate, is permeable to water vapor and oxygen, but impermeable to water and bacteria. The dressing provides a moist environment upon the surface of the wound and provided that it is not allowed to dry out, the dressing will not adhere to the underlying tissue upon removal.

moosejaw.com

氨基酸洗面皂全 成 份 Dis Water 、 Sodium Lauroyl Glutamate 、 Polyethylene Glycol 400 、 Potassium Laurate 、 1-3Butylene Glycol 、 Methyl Paraben 、 Propyl Paraben 、Perfume

成份說明 ◎ 聚乙二醇 400(Polyethylene Glycol 400) ：界面活性劑，防止水分過度流失。Compete-cosmetic.com

PPO Application

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PEO-b-PPO-b-PEO triblock copolymer (Pluronic@): micelles in water because of hydrophilic PEO and hydrophobic PPO

O

EO units

HO

H

Hydrogen bonding

O

PO units

HO

methyl screening

H

CHH

H

Mesoporous silica as a catalyst substrateFrom. myoops.org

PTHF Application

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PU Chemistry:

PU Structures: Hard domain (aggregation of urethane units via Hydrogen bonding) and soft domain (chain entanglement of alkoxide chains (PTHF) between urethane).

PU Elastomers: Hard domains are used to keep the shape of elastomers and soft domains are used to extend when external force is applied.

diisocyanate diol Urethane linkages

From wikipedia.org

Foaming

Monomer 2

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Imine & sulfide: N- & S-cyclic monomersCationic ROP polymerization only for cyclic

imine monomers

Acetal: O&C-alternate cyclic monomers Cationic ROP polymerization only for cyclic

acetal monomers

NH

CH2 CH2

CH2 CH2

CH2 N H

CH2 CH2S

CH2 CH CH3S

CH2

CH2 CH2

S

RC

R

CH2

CH2S

CH2 OCH2O

CH2

CH2

OO

CH2 CH2

O

CH2

O O

Polyacetal Application

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Polyoxymethylene (POM): engineering thermoplastic, high stiffness, low friction and excellent dimensional stability.

Five engineering thermoplastic: Polyamide (PA, i.e., Nylon 6), POM, polycarbonate (PC, CD substrate), polyphenylene oxide (PPO), Polybutylene terephthalate (PBT).

From wikipedia.orgUsed for guitar picks

Monomer 3

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Cyclic ester monomers:

O

O

R OH +

Sn(Oct)2or AlEt3/Toluene

R OO

OHn

OO

O

O

e-caprolactone

R OH +

Sn(Oct)2or AlEt3/Toluene

R OO

O

Hn

lactide

PCL

PLAO

O

PLA cups PLA bags

OH

O

OH

lactic acidCorn Fermentation

From wikipedia.org

PCL scaffold for tissue engineering

Monomer 4

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Polyphosphazenes:A flame retardant Materials

PN P

NPNR R

RR

RR R

O COOH

:

ROP

50wt% Char Yield !!

1000 oC flameblack char

From research.chem.psu.edu

Monomer 5

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Silicon ( 矽利康 )Silicon Oil: Polydimethylsiloxane (PDMS)

Silicon Oil (PDMS)

Lubrication

Viscosity of PDMS depends on Mn !!

Silicon Ruber Hose

OSiO

SiOSi O

Si n

PDMS

crosslinkingSilicon Rubbers

ROP

Summary

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Polymerization without new bonds: cyclic monomers to linear polymer.

Ionic initiator or using metal catalyst (coordination)

The ring opening polymerization is developed to improve the condensation polymerization by combination of radical polymerization behavior--- initiation.

Common ROP polymers: Nylon 6, PEO, PPO, PTHF, POM, PCL, PLA, Polyphosphazenes, PDMS.

A chemist should remember the chemical names and the chemical structures of common ROP polymers.

Thanks for Your attention