Toughening of Unsaturated Polyesters by Reactive Liquid Polymers. 2. Processibility and Mechanical Properties

1994 ◽  
Vol 33 (11) ◽  
pp. 2778-2788 ◽  
Author(s):  
Sandeepak B. Pandit ◽  
Vikas M. Nadkarni
Keyword(s):  
Mechanical Properties ◽  
Unsaturated Polyesters ◽  
Liquid Polymers ◽  
Reactive Liquid

scholarly journals Cross-Linkable Epoxidized Maleinated Castor Oil: A Renewable Resin Alternative to Unsaturated Polyesters

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Yeşim Müge Şahin ◽  
Gökhan Çaylı ◽  
Jesmi Çavuşoğlu ◽  
Emre Tekay ◽  
Sinan Şen
Keyword(s):  
Mechanical Properties ◽  
Castor Oil ◽  
Unsaturated Polyester ◽  
Mechanical Analysis ◽  
Carboxyl Groups ◽  
Spectroscopic Techniques ◽  
Thermal And Mechanical Properties ◽  
Unsaturated Polyesters ◽  
H Nmr ◽  
And Storage

As an alternative resin to conventional synthetic unsaturated polyesters (UPEs), epoxidized maleinated castor oil (EMACO) was synthesized in two steps. For this purpose, castor oil was reacted with maleic anhydride at 70°C to obtain maleinated castor oil (MACO). Then, epoxidation of MACO was carried out by using a mixture of formic acid and hydrogen peroxide at 0–5°C. Then, the free carboxyl groups of the synthesized EMACO were further reacted with free epoxide groups of EMACO at 90°C. At the end of the reaction, an unsaturated polyester precursor-prepolymer was obtained (P-EMACO). FTIR and1H NMR spectroscopic techniques were used to characterize the monomers synthesized. The P-EMACO was then mixed with styrene and cross-linked in the presence of AIBN at 50°C. Thermal and mechanical properties of the final cross-linked product were investigated by thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) techniques. The degradation onset temperature of the material at which cross-linked X-EMACO loses 5% of its weight was found to be 209°C. Its dynamicTgand storage modulus at 25°C were determined as 72°C and 1.08 GPa, respectively. These results are higher than some of the different oil based polymers reported in the literature.

Amine Terminated Reactive Liquid Polymers; Modification of Thermoset Resins

1981 ◽  
Vol 54 (2) ◽  
pp. 374-402 ◽  
Author(s):  
C. K. Riew
Keyword(s):  
Molecular Weight ◽  
Elevated Temperatures ◽  
Average Molecular Weight ◽  
Impact Resistance ◽  
Secondary Amide ◽  
Amine Group ◽  
Low Viscosity ◽  
End Groups ◽  
Liquid Polymers ◽  
Reactive Liquid

Abstract Amine terminated reactive liquid polymers (AT-RLP) are synthesized from corresponding carboxyl terminated reactive liquid polymers (CT-RLP) and diamines. The CT-RLPs have a functionality of close to two, the average molecular weight ranging from 2500 to 4000, and Brookfield viscosity ranging from 30 to 600 Pa · s at 27°C. AT-RLPs made from the CT-RLPs have about the same physical properties as the CT-RLPs given above. N-(2-aminoethyl)piperazine (AEP2) is the best diamine among the diamines tried to produce low viscosity and low molecular weight AT-RLPs. Structure of end-groups of AT-RLP is unequivocally identified as a secondary amide and a secondary amine group resulting from the reaction of carboxyl end-groups of CT-RLP and a primary amine group of AEP,. The AT-RLP can be used as a modifier for epoxy resins at room or elevated temperatures to produce castable formulations with properties ranging from plastics to elastomers. The formulations may be useful as a modifier for improvement of crack and/or impact resistance of normally brittle epoxy plastics, as castable elastomers, paints and coatings, sealants, adhesives, especially as solventless adhesives for conveyor belts, hoses, shoes, and as binders for woven or non-woven fibers and cords.

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