Preliminary adhesive and composite properties of LARC™-CPI 2, a new semicrystalline polyimide

1993 ◽  
Vol 5 (3) ◽  
pp. 177-185 ◽  
Author(s):  
P M Hergenrothert ◽  
S J Havens
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Glass Transition ◽  
Transition Temperature ◽  
High Performance ◽  
Melt Temperature ◽  
High Molecular Weight Form ◽  
Aerospace Applications ◽  
Composite Properties ◽  
Molecular Weight Form

In continuation of an effort to develop processable high-performance structural resins for use in aerospace applications, a new polyimide. LARCTM-CPI 2, has been developed. This semicrystalline polyimide was prepared by the reaction of 4.4'-oxydiphthalic anhydride with 1,4-bis(4-aminophenoxy-4'-benzoyl)benzene. In high-molecular-weight form this material has a glass transition temperature of 223 C and a crystalline melt temperature of approximately 350 'C. Controlled-molecular-weight end-capped versions of LARCTM-CPI 2 were used to fabricate adhesive panels and composites that exhibited good mechanical properties at temperatures as high as 200 C.

Scale-up of Poly[(Vinyl Chloride)-b-(n-Butyl Acrylate)-b-(Vinyl Chloride)] prepared by Living Radical Polymerization

2006 ◽  
Vol 514-516 ◽  
pp. 975-979 ◽  
Author(s):  
Jorge F.J. Coelho ◽  
Patricia Alves ◽  
Joana Monteiro ◽  
M. Margarida C.A. Castro ◽  
Mariana Abreu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Radical Polymerization ◽  
Vinyl Chloride ◽  
Scale Up ◽  
Living Radical Polymerization ◽  
Poly Vinyl Chloride

Vinyl Chloride (VCM) based copolymers were synthesised by using Living Radical Polymerization. The obtained materials were characterized by determining their molecular weight, glass transition temperature and mechanical properties after processing in industrial equipments. Their chemical composition was evaluated by using NMR.

Effects of ingredient proportions on the performance of α-Cellulose/PLA mixtures used for laser sintering

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5886-5898 ◽  
Author(s):  
Hui Zhang ◽  
Yanling Guo ◽  
David L. Bourell ◽  
Deyu Meng
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Processing Parameters ◽  
Laser Sintering ◽  
Cellulose Powder ◽  
Melt Temperature ◽  
Powder Feedstock ◽  
Biomass Materials ◽  
Sustainable Materials

A new powder feedstock composed of biocompatible and degradable biomass materials was introduced and evaluated for laser sintering in this research. The goal for the material is to facilitate high-value utilization of sustainable materials and expand the variety of feedstock that can be used for laser sintering. It was mechanically mixed with polylactic acid (PLA) powder and the filler of α-cellulose powder in the content of 5 wt%, 10 wt%, 15 wt%, and 20 wt%. The effects of the ingredient proportions were evaluated relative to laser sintering performance of α-cellulose/PLA mixtures. The results revealed that the increasing cellulose loading had almost no influence on the mixtures’ glass transition temperature, the melt temperature, and the crystallization temperature; thus, the mixtures would share the same processing parameters with neat PLA during the laser sintering fabrication. Although the cellulose loading reduced the materials’ melt fluidity and mechanical properties, it decreased the dimensional deformation of the laser-sintered parts and made the mixture more feasible as the feedstock of laser sintering compared to neat PLA.

scholarly journals Studies on the Modification of Commercial Bisphenol-A-Based Epoxy Resin Using Different Multifunctional Epoxy Systems

2021 ◽  
Vol 2 (2) ◽  
pp. 419-430
Author(s):  
Ankur Bajpai ◽  
James R. Davidson ◽  
Colin Robert
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Bisphenol A ◽  
Epoxy Resin ◽  
Tensile Fracture ◽  
Chemical Structures ◽  
Amino Phenol ◽  
Epoxy Systems

The tensile fracture mechanics and thermo-mechanical properties of mixtures composed of two kinds of epoxy resins of different chemical structures and functional groups were studied. The base resin was a bi-functional epoxy resin based on diglycidyl ether of bisphenol-A (DGEBA) and the other resins were (a) distilled triglycidylether of meta-amino phenol (b) 1, 6–naphthalene di epoxy and (c) fluorene di epoxy. This research shows that a small number of multifunctional epoxy systems, both di- and tri-functional, can significantly increase tensile strength (14%) over neat DGEBA while having no negative impact on other mechanical properties including glass transition temperature and elastic modulus. In fact, when compared to unmodified DGEBA, the tri-functional epoxy shows a slight increase (5%) in glass transition temperature at 10 wt.% concentration. The enhanced crosslinking of DGEBA (90 wt.%)/distilled triglycidylether of meta-amino phenol (10 wt.%) blends may be the possible reason for the improved glass transition. Finally, the influence of strain rate, temperature and moisture were investigated for both the neat DGEBA and the best performing modified system. The neat DGEBA was steadily outperformed by its modified counterpart in every condition.

scholarly journals Synthesis, Properties, and Biodegradability of Thermoplastic Elastomers Made from 2-Methyl-1,3-propanediol, Glutaric Acid and Lactide

Life ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 43
Author(s):  
Lamya Zahir ◽  
Takumitsu Kida ◽  
Ryo Tanaka ◽  
Yuushou Nakayama ◽  
Takeshi Shiono ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Glutaric Acid ◽  
Triblock Copolymers ◽  
Tensile Tests ◽  
Thermoplastic Elastomers ◽  
Proteinase K ◽  
Synthesis Properties

An innovative type of biodegradable thermoplastic elastomers with improved mechanical properties from very common and potentially renewable sources, poly(L-lactide)-b-poly(2-methyl-1,3-propylene glutarate)-b-poly(L-lactide) (PLA-b-PMPG-b-PLA)s, has been developed for the first time. PLA-b-PMPG-b-PLAs were synthesized by polycondensation of 2-methyl-1,3-propanediol and glutaric acid and successive ring-opening polymerization of L-lactide, where PMPG is an amorphous central block with low glass transition temperature and PLA is hard semicrystalline terminal blocks. The copolymers showed glass transition temperature at lower than −40 °C and melting temperature at 130–152 °C. The tensile tests of these copolymers were also performed to evaluate their mechanical properties. The degradation of the copolymers and PMPG by enzymes proteinase K and lipase PS were investigated. Microbial biodegradation in seawater was also performed at 27 °C. The triblock copolymers and PMPG homopolymer were found to show 9–15% biodegradation within 28 days, representing their relatively high biodegradability in seawater. The macromolecular structure of the triblock copolymers of PLA and PMPG can be controlled to tune their mechanical and biodegradation properties, demonstrating their potential use in various applications.

Semi-bio-based aromatic polyamides from 2,5-furandicarboxylic acid: toward high-performance polymers from renewable resources

RSC Advances ◽  
2016 ◽  
Vol 6 (90) ◽  
pp. 87013-87020 ◽  
Author(s):  
Kaiju Luo ◽  
Yan Wang ◽  
Junrong Yu ◽  
Jing Zhu ◽  
Zuming Hu
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
Renewable Resources ◽  
High Performance ◽  
Good Thermal Stability ◽  
Aromatic Polyamides ◽  
High Performance Polymers ◽  
Furandicarboxylic Acid

Aromatic furanic polyamides with relatively high molecular weight were synthesized, and good thermal stability and mechanical properties were demonstrated.

Imide Oligomers Containing Pendent and Terminal Phenylethynyl Groups—II

1998 ◽  
Vol 10 (3) ◽  
pp. 273-283 ◽  
Author(s):  
J W Connell ◽  
J G Smith ◽  
P M Hergenrother
Keyword(s):  
Molecular Weight ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Average Molecular Weight ◽  
Adhesive Tape ◽  
High Glass Transition Temperature ◽  
Compressive Properties ◽  
Compression Moulding ◽  
Imide Oligomers

As part of a programme to develop high-performance/high-temperature structural resins for aeronautical applications, imide oligomers containing pendent and terminal phenylethynyl groups were prepared, characterized and the cured resins evaluated as composite matrices. The oligomers were prepared at a calculated number-average molecular weight of 5000 g mol−1 and contained 15–20 mol% pendent phenylethynyl groups. In previous work, an oligomer containing pendent and terminal phenylethynyl groups exhibited a high glass transition temperature (∼313 °C), and laminates therefrom exhibited high compressive properties, but processability, fracture toughness, microcrack resistance and damage tolerance were less than desired. In an attempt to improve these deficiencies, modifications in the oligomeric backbone involving the incorporation of 1,3-bis(3-aminophenoxy)benzene were investigated as a means of improving processability and toughness without detracting from the high glass transition temperature and high compressive properties. The amide acid oligomeric solutions were prepared in N-methyl-2-pyrrolidinone and were subsequently processed into imide powder, thin films, adhesive tape and carbon fibre prepreg. Neat resin plaques were fabricated from imide powder by compression moulding. The maximum processing pressure was 1.4 MPa and the cure temperature ranged from 350 to 371 °C for 1 h for the mouldings, adhesives, films and composites. The properties of the 1,3-bis(3-aminophenoxy)benzene modified cured imide oligomers containing pendent and terminal phenylethynyl groups are compared with those of previously prepared oligomers containing pendent and terminal phenylethynyl groups of similar composition and molecular weight.

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