Posts

Showing posts with the label Biocomposites

Experiment: Make Binding Forces Visible- Molecular Binding Forces, Recycling/Reuse, Life Cycle Engineering (LCE)

Image
       JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract A very simple experiment shows students the difference between primary and secondary molecular binding forces. Use an empty plastic cup for milk, yoghurt or coffee and destroy it by pressing the cup together. You will watch cracks only longitudinal the cup. Try to break the cup horizontally you will fail. What you observe are the secondary binding forces between the molecules oriented along the length of the cup versus the primary binding forces perpendicular to the long side of cup. Keywords:  Molecular Binding Forces; Recycling/Reuse; Life Cycle Engineering (LCE) Introduction What should be found/investigated ? [answer: Are the primary molecular binding forces (within the molecular chain acting binding forces, i.e. between primarily connected atoms) actually significantly stronger than the secondary binding forces (between molecules acting forces)? How can a yoghurt cup be reused in...

Polymer Engineering - Developing or Improving Plastic Products- Are Plastics Boon or Bane?

Image
         JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Plastics have advantages and disadvantages in properties like every other material section i.e. wood, metals, aluminum, ceramics. A boon is the high flexibility with plastics to create each desired property for each single application. But this is exactly also the bane. The result are the 5 Billon tons of plastic worldwide everywhere on earth. The diversity of plastic solutions is enormous. This makes reuse of it almost impossible. Compared with no economic value of used plastic the significance for Consumers and companies is almost zero. We need a common strength to solve this problem. And we need true facts from scientists and experts to help consumers make the wright decision under technical, economical, ecological and social aspects. This is shown in detail using a plastic tote bag versus a fiber tote bag. Keywords:  Polymer Engineering; Plastic Products; Advantages and Dis...

Synthesis and Radical Copolymerization of Novel Phenyl-Disubstituted Propyl Cyanoacrylates- Juniper Publishers

Image
                                        JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Novel phenyl-disubstituted propyl 3-(R-phenyl)-2-cyanoacrylates, RPhCH=C(CN)CO 2 C 3 H 7 (where R is 2-fluoro-5-methyl, 3-iodo-4-methoxy, 5-iodo-2-methoxy, 3,5-dichloro, 3,4-difluoro, 3,5-difluoro, 2-chloro-4-fluoro, 2-chloro-6-fluoro, 3-chloro-2-fluoro, and 3-chloro-4-fluoro) were prepared using condensation of substituted benzoic aldehydes and propyl ester of cyanoacetic acid. The ethynyl benzene copolymerization of novel cyanoacrylates was conducted in solution with radical initiation at 70 C. Nitrogen analysis, 1 H & 13 C NMR was used to analyze composition and the structure. Thermal behavior of the copolymers was analyzed by DSC and TGA. Keywords: Radical copolymerization; Styrene copolymers; Trisubstituted ethylene’s; Cyanoacrylates ...

Cationic Polymerization of Para-Methyl Styrene- Juniper Publishers

Image
                                       JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Cationic polymerization of p-methyl styrene by phenacyl triphenyl phosphonium, phenacyl triphenyl arsonium and p, p`-bis[(triphenylphosphonio) methyl benzophenone salts [1-3], and cation radical salt of p-substituted triphenylamine having different p-substilments was carried out photochemically and/or thermally. Cation radical amine salts were found to be more effective thermally in comparison to phosphonium or arsonium salts. The effects of initiator structure, counter ion, concentrations of salts and reaction conditions on the rate of polymerization in dichloromethane on the isolated polymer will be presented Figure 1-3. Keywords:  Phenacyl triphenylphosphonium salts; Phenacyl triphenylparsonium salts; tri p-substituted triphenyl amine salts; p-methyl styrene;...

Formulation and Characterization of Glutathione-Loaded Bioadhesive Hydrogel for Ocular Delivery-Juniper Publishers

Image
                                   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Glutathione may prevent age-related, oxidative damage to ocular tissues but has poor corneal penetration. Hydrogel formulations were investigated to determine an optimized ocular delivery system. The rheology and texture profile of formulations were investigated at 25°C. The 1% w/v glutathione was incorporated into systems demonstrating desirable characteristics for ocular vehicles and physical characteristics re-determined. In vitro cumulative glutathione delivery across the bovine cornea was measured over 8 hours at 32ÂșC in Franz diffusion cells. Carbopol-containing Poloxamer systems exhibited shear-thinning behavior desirable for ocular formulations whilst Polyvinyl alcohol (PVA) and Polyacrylic acid (PAA) systems exhibited Newtonian behavior. Of the glutathione-containing ...