Juniper Publishers Journal of Polymer science

  Academic Journal of Polymer Science - Juniper Publishers                                                                     Abstract Membrane technology offers a wide range of applications and advantages in many fields. On the other hand, PEEK-WC is widely employed to produce membranes, also after chemical modifications, with different morphologies and different techniques, and for many applications. In this work transparent PEEK-WC membranes were produced, modifying just the preparation conditions. Transparent membranes find a lot of applications, from display protection film, in odontology, as impermeable pellicles, in cultural heritage protection, but also in traditional fields, as gas separation. Not all the membranes are transparent, but it seems clear that the oxygen presence during membrane formation is r...

   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract The significant access to the structurally pure, high molar mass, N-containing polymers via palladium-catalyzed polycondensation of various aromatic diamines with various aromatic dibromo compounds is an interesting target. One of the major advantages is to apply inexpensive monomers; aromatic amines and aromatic bromides. Furthermore, many diamines are readily available or easy to synthesize giving fast access to numerous new functionalized polymers either by applying amino-functionalized or bromo-functionalized monomers to optimize and improve the polymer properties. With the increasing demand for different functionalized polymers, the focus of relevant studies has been to generate polymers with improved properties by palladium-catalyzed polycondensation. A series of poly(imino ether)s (PIEs), poly(imino ketone)s (PIKs), poly(imino azobenzene)s (PIAzos), poly(imino acridine)s (PIAcs), poly(imino fluor...

       JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract IThis study highlights how the transition from uncured to cured state in rubber is characterized by the formation of a particular network structure, so-called critical gel. Critical gel is formed in the first stages of vulcanization and is independent by the macromolecular structure and crosslinking. Keywords:  Curing cycle design; Under-cure phase; Spongelike region; Blowing point; Shrinkage; Critical Gel time; Elastomer; Compound; Viscoelasticity Introduction Vulcanization proceeds through three different stages, as shown in Figure 1. The first stage is characterized by an induction phase in which the reactions between the curatives and macromolecules of the polymeric matrix take place. In the second, commonly known as curing stage, cross-linking reactions between the macromolecular chains take place [1-2]. The initial sol-gel transition is characterized by the formation of a “criti...

     JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Ion exchange membranes (IEMs) are used for exchanging or removing ions from the solutions so that they are fabricated by polymers rather than metals or ceramics. When metal is in contact with the solutions, some reaction or corrosion occurs, and ceramic is difficult to use in membrane form because it is brittle. Also, normal metals and ceramics do not have high ion-exchange properties so that polymers are used widely as a host material of the IEM. The conventional IEMs are either layered membrane consisted of ion exchange material and support layer, and thick bulk membrane. There are no critical problems to use them for water treatment, but they are not suitable for electrochemical application such as reverse electrodialysis (RED). RED is a method of making electricity by sequential ion transport through semi-permeable membranes and electrochemical reaction at the electrode part so that the IEMs ...