Resilient Poly(α-hydroxy acids) with Improved Strength and Ductility via Scalable Stereosequence-Controlled Polymerization

2021 ◽  
Author(s):  
Xiaoqian Wang ◽  
Ai Lin Chin ◽  
Jingyi Zhou ◽  
Hua Wang ◽  
Rong Tong
Keyword(s):  
Hydroxy Acids ◽  
Controlled Polymerization ◽  
Strength And Ductility

scholarly journals Controlled Ring-Opening Polymerization of O-Carboxyanhydrides to Synthesize Functionalized Poly(α-Hydroxy Acids)

2021 ◽  
Vol 03 (01) ◽  
pp. 041-050
Author(s):  
Xiaoqian Wang ◽  
Ai Lin Chin ◽  
Rong Tong
Keyword(s):  
Biomedical Engineering ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Metal Catalyst ◽  
Hydroxy Acids ◽  
Controlled Polymerization ◽  
Biodegradable Polyesters ◽  
Recent Advances

Poly(α-hydroxy acids), as a family of biodegradable polyesters, are valuable materials due to their broad applications in packaging, agriculture, and biomedical engineering. Herein we highlight and explore recent advances of catalysts in controlled ring-opening polymerization of O-carboxyanhydrides towards functionalized poly(α-hydroxy acids), especially metal catalyst-mediated controlled polymerization. Limitations of current polymerization strategies of O-carboxyanhydrides are discussed.

Direct Observation of Chain Lengths and Conformations in Oligofluorene Distributions from Controlled Polymerization by Double Electron-Electron Resonance

2019 ◽  
Author(s):  
Dennis Bücker ◽  
Annika Sickinger ◽  
Julian D. Ruiz Perez ◽  
Manuel Oestringer ◽  
Stefan Mecking ◽  
...  
Keyword(s):  
Chain Length ◽  
Length Distribution ◽  
Catalyst System ◽  
Chain Conformation ◽  
Controlled Polymerization ◽  
Chain Length Distribution ◽  
Electron Resonance ◽  
Double Electron ◽  
The Individual ◽  
Double Electron Electron Resonance

Synthetic polymers are mixtures of different length chains, and their chain length and chain conformation is often experimentally characterized by ensemble averages. We demonstrate that Double-Electron-Electron-Resonance (DEER) spectroscopy can reveal the chain length distribution, and chain conformation and flexibility of the individual n-mers in oligo-(9,9-dioctylfluorene) from controlled Suzuki-Miyaura Coupling Polymerization (cSMCP). The required spin-labeled chain ends were introduced efficiently via a TEMPO-substituted initiator and chain terminating agent, respectively, with an in situ catalyst system. Individual precise chain length oligomers as reference materials were obtained by a stepwise approach. Chain length distribution, chain conformation and flexibility can also be accessed within poly(fluorene) nanoparticles.

ANACONDA ALLOY 360

Alloy Digest ◽  
1982 ◽  
Vol 31 (11) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
High Speed ◽  
Heat Treating ◽  
High Speed Machining ◽  
Copper Base ◽  
Screw Machine ◽  
Medium Strength ◽  
Machining Operations ◽  
Strength And Ductility

Abstract ANACONDA Alloy 360 is a leaded brass and is the alloy most often used for high-speed machining operations; it fills most of the needs for such purposes. Alloy 360 is the standard free-cutting brass and its machinability has become the standard by which all other copper-base alloys are rated. It has medium strength and ductility. Alloy 360 is used for hardware such as gears and pinions where excellent machinability is of prime importance and for all types of automatic high-speed screw-machine products. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-447. Producer or source: Anaconda American Brass Company.

COPPER ALLOY No. C84200

Alloy Digest ◽  
1982 ◽  
Vol 31 (10) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Copper Alloy ◽  
Heat Treating ◽  
Lead Alloy ◽  
Good Resistance ◽  
Copper Zinc ◽  
Pipe Fittings ◽  
Strength And Ductility

Abstract Copper Alloy No. C84200 is a free-cutting copper-zinc-tin-lead alloy. It is characterized by good casting properties, moderate strength and ductility, good machinability and good resistance to corrosion. Formerly used named (not recommended) are 101, Leaded Semi-Red Brass and 80-5-2.5-12.5. Typical applications are pipe fittings, bushings, locknuts and unions. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-446. Producer or source: Copper alloy foundries. See also Alloy Digest Cu-450, December 1982.

COPPER ALLOY No. C44400 and C44500

Alloy Digest ◽  
1994 ◽  
Vol 43 (11) ◽  
Keyword(s):  
Fracture Toughness ◽  
Copper Alloy ◽  
Heat Treating ◽  
Small Addition ◽  
Good Combination ◽  
General Corrosion ◽  
Good Resistance ◽  
Tin Alloys ◽  
Copper Zinc ◽  
Strength And Ductility

Abstract COPPER ALLOY NOS. C44400 and C44500 are copper-zinc-tin alloys inhibited by antimony and phosphorus, respectively. They are commonly known as inhibited admiralty metal or admiralty brass. They have a good combination of strength and ductility and good resistance to general corrosion. The small addition of inhibitor is made to minimize the alloy’s susceptibility to dezincification and stress corrosion. They are used for condenser, evaporator and heat-exchanger tubes and associated applications. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and creep. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: CU-599. Producer or source: Copper and copper alloy mills.

APEX 417

Alloy Digest ◽  
1958 ◽  
Vol 7 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Physical Properties ◽  
Dimensional Stability ◽  
High Strength ◽  
Heat Treating ◽  
Casting Alloy ◽  
Excellent Corrosion Resistance ◽  
Magnesium Casting ◽  
Strength And Ductility

Abstract APEX 417 is an aluminum-magnesium casting alloy having high strength and ductility, excellent corrosion resistance and good dimensional stability. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and fatigue. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Al-61. Producer or source: Apex Smelting Company.

COPPER ALLOY No. 844

Alloy Digest ◽  
1978 ◽  
Vol 27 (3) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Copper Alloy ◽  
Heat Treating ◽  
Zinc Alloy ◽  
Good Resistance ◽  
Lead Zinc ◽  
Strength And Ductility

Abstract Copper Alloy No. 844 is a free-cutting copper-tin-lead-zinc alloy for castings; it was formerly identified as 81-3-7-9 alloy. It is characterized by good casting properties, moderate strength and ductility, good machinability and good resistance to corrosion. It is used widely for fittings, plumbing goods and valves. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-349. Producer or source: Copper alloy foundries.

ALUMINUM 5056

Alloy Digest ◽  
1979 ◽  
Vol 28 (2) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Shear Strength ◽  
High Strength ◽  
Heat Treating ◽  
Chromium Alloy ◽  
Temperature Performance ◽  
Wrought Aluminum ◽  
Strength And Ductility ◽  
Cold Workability ◽  
Manganese Chromium

Abstract ALUMINUM 5056 is a non-heat-treatable wrought aluminum-magnesium-manganese-chromium alloy possessing high strength and ductility along with good hot and cold workability. It is recommended for such applications as rivets and screen wire. It may be used with or without cladding. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Al-126. Producer or source: Various aluminum companies. Originally published June 1963, revised February 1979.

BRIDGEPORT 54

Alloy Digest ◽  
1964 ◽  
Vol 13 (5) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Physical Properties ◽  
Tensile Properties ◽  
Erosion Resistance ◽  
Heat Treating ◽  
Good Strength ◽  
High Corrosion ◽  
Copper Zinc ◽  
Strength And Ductility

Abstract Bridgeport 54 is a copper-zinc-aluminum alloy having high corrosion and erosion resistance combined with good strength and ductility. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as heat treating and machining. Filing Code: Cu-141. Producer or source: Bridgeport Brass Company.

Sign in / Sign up

Export Citation Format

Share Document