Juniper Publishers Journal of Polymer science

                                                  JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Opinion The sulfur cure system in the ethylene-propylene-diene (EPDM)-based Curtain Wall Seal (CWS) has two accelerators, adding up to 2.75 parts per hundred rubber (phr) by weight, and two activators (ZnO: 5phr, stearic acid:1phr) [1]. In total, 8.75phr chemicals are used to fully cure the article with 1phr elemental sulfur. In rubber formulations, chemical curatives are indispensable and once reacted with sulfur at elevated temperature, they produce crosslinks between the rubber chains and provide shape stability, which is essential for the performance, durability and life of the final product in service. Excessive use of chemical curatives is harmful to health, safety, and the environment. According to the European Directive 67/548/E...

                                         JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract In the present work, triple base propellant (TBP) containing mainly energetic nitrate polymer nitrocellulose and nitroglycerine, picrite, 1,1-diamino-2,2-dinitroethene (FOX-7) along with ingredients such as stabiliser and plasticizer has been processed by solvent method. Picrite has been replaced in increments with FOX-7 from the propellant composition. Acetone: ethanol used as solvent to gelatinise/plasticize NC during processing. Dimensions of the propellant was determined by physical measurement and propellant grains were subjected to mechanical properties (compressive strength (CS), % compression) determination, sensitivity tests and closed vessel (CV) firing. Incorporation of FOX-7 led to remarkable increase in CS at sub-zero temperatures (-20°C) and ...

                                          JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract The polymerization of 4-vinyl-1-cyclohexene diepoxide (4-VCHD) by rhenium carbonyl, Re(CO)5X (X = Br, Cl) and dirhenium decacarbonyls Re 2 (CO) 10 has been carried out photochemically at 25oC, and thermally at 25 and 75oC witout cocatalysts. The effects of initiator structure, concentrations, and reaction temperature and time on the polymerization rate is reported here. Keywords: 4-vinyl-1-cyclohexene diepoxide; Rhenium Carbonyl; Photoinitiated Polymeriation Introduction Diepoxy resins have found important commercial applications in UV radiation curing of surface coatings; a dhesives and in the plastic industry [1,2]. Photoinitiated cationic ring-opening polymerizations of cyclohexene oxide (CHO)1 (Figure 1)...

JUNIPER PUBLISHERS- ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Thermoplastic copolyesters (TPE-Es) are multi-block copolymers commonly incorporating hard (polyester) and soft (polyether) blocks. Multifunctional epoxy-based chain extenders (TGDDM) are one of the additives that serve to reverse molecular weight (M W ) damage caused by the process of hydrolysis of TPE-E. There are two functional groups that are capable of additional reactions on the terminal hydroxyl and carboxyl groups of TPE-E. Considering the hydrogen bonded hard segments in hard domains are less susceptible to hydrolysis compared to the non-hydrogen bonded equivalents, the phase separated morphology of polyether-polyester copolymers based TGDDM also provides to the long-term stability. The molecular weight of TPE-E was determined by GPC and the thermal and tensile behaviors were investigated. Keywords: Thermoplastic copolyester; Crosslinking; Hydrolysis; Mechanical properties Abbrevations: ...