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Mineral fillers like talc and mica are commonly used in the plastic industry because of their tendency to alter the properties of thermoplastic materials. Polypropylene (PP)-talc (PTC), PP-mica (PMC), and PP-talc/mica hybrid composites (PHC) were prepared. Results indicated that filler particle size, type, and content greatly influence the mechanical and rheological properties of the composites. Shear viscosity decreased with the increase in shear rate. At 40°C, an increase of approximately 120% in storage modulus ( E′) was observed in PMC composites. C parameter increased, whereas reinforcing efficiency ( r) decreased with the increase in filler loading. Percent elongation of each type of composites decreased with the increase in filler loading. Tensile modulus of PTC composite increased significantly by 103% (571 MPa) at 20% loading of talc, whereas for PHC and PMC composites, increase of 93% (543 MPa) and 81% (511 MPa) was observed. Flexural modulus also increased considerably by 88% (2413 MPa), 80% (2313 MPa), and 62% (2084 MPa) of PTC, PHC, and PMC composites at 20% filler loading.

Polypropylene composites were prepared using natural fibers such as pigeon pea stalk fibers and banana peel. Aerobic biodegradation studies in compost have been carried out as per ASTM with composites prepared where cellulose and polypropylene has been taken as positive and negative reference respectively. Various analytical tools like SEM, TGA, XRD, DSC and Color have been used to study the change after biodegradation in composites. Highest fiber loaded composites i.e. 40 wt% depicted highest biodegradation in comparison to 10 and 20 wt% loading of untreated fiber in polypropylene. In comparison to untreated fiber composites, maximum biodegradation was observed in treated fiber composites with same amount of the fiber loading.

VoIP has become an interesting topic of research in both the internet and the telecommunication industry. The tremendous increase in popularity of VoIP services is a result of huge growth in broadband access. In wired as well as in wireless communication, VoIP is expected to completely replace the traditional telephony approaches. To provide a good quality speech through VoIP applications, certain QoS parameters must be analyzed. These QoS parameters help us to evaluate the performance of various networking protocols, voice encoding schemes, etc. Numbers of QoS techniques like IntServ, DiffServ and RSVP are adopted to ensure good quality in IP based networks. In this paper, our main contribution is to analyze and evaluate the performance of various voice encoding schemes using RSVP, in a VoIP based wireless LAN. The network model designed in this paper is based on OPNET IT GURU Academic Edition. Various scenarios for different voice encoding schemes using RSVP are setup in the OPNET simulation environment. Different parameters that indicate the QoS like throughput, end to end delay, delay variations, traffic send, traffic received, etc. are calculated and analyzed in WLAN.