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Polylactide (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and sugar beets, has attracted much attention for automotive parts application. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the PLA composites including stereocomplexed with L- and D-PLA, we developed the unit processes such as fermentation, separation, lactide conversion, and polymerization. We investigated D-lactic acid fermentation with a view to obtaining the strains capable of producing D-lactic acid, and through catalyst screening test for polycondensation and depolymerization reactions, we got a new method which shortens the whole reaction time of lactide synthesis step. Poly(d-lactide) is obtained from the ring-opening polymerization of d-lactide. Also we investigated several catalysts and polymerization conditions.

The main contribution of this paper is to employ a sound and vibration theory in order to develop a light and cost effective plastic intercooler pipe. The intercooler pipe was composed of two rubber hoses and one aluminum pipe mounted between an ACV (Air Control Valve) and an intercooler outlet. The engineering design concept is to incorporate low-vibration type bellows and an impedance-mismatched center pipe, which replaces the rubber hoses and aluminum pipe respectively. The bellows were designed to adapt powertrain movement for high vibration transmission loss to the intercooler outlet. Also, the impedance-mismatched center pipe was implemented to increase reflected wave by using relatively higher modulus than bellows part and applying a SeCo (Sequential Coextrusion) processing method.

Today, all manufacturers of vehicles are up for the challenge to abide in automobile emission control laws. Weight reduction is one of the best solutions to reduce both fuel consumption and emissions. The most effective method for the said idea is to have lightweight materials to some parts of vehicle using the FRP(Fiber Reinforced Plastics). In order to obtain good mechanical properties of FRP, continuous fiber should be used. But it is difficult to design and manufacture FRP parts using continuous fiber because of material properties and molding process. In this paper, it is used CF(carbon Fiber) and Epoxy to make a composite material. Properties of this CFRP can be predicted through analysis. Tests and simulations of specimen are performed as every step progresses for correlation. A spring can be designed to meet all requirements for specific performance. The CFRP spring is made by new devices and methods and can be applied to vehicle for practical use.

Anti-vibration rubbers in vehicle play an important role in restricting vibration generated from engine and road. But, degradation occurs when rubber is exposed for a long time to heat, light, ozone and etc. These make the rubber hard and lose its initial properties. The rubber change makes N.V.H performance of vehicle the worse, and gives the discomfort to the passengers. To reduce the change of rubber properties, sulfur-donor and heat stable cross-linking co-agent vulcanization system have been introduced in the developed natural rubber compounds of the anti-vibration rubber parts. These lead to a reduction of degradation of material properties, maintenance of the initial properties and increase of the fatigue life.

A new thermoplastic polyolefin with primerless adhesion to paint has been developed by polypropylene (PP) with α-olefin copolymers, mineral fillers and some additives. It can substantially reduce costs and environmental problems by eliminating primer treating operations, traditionally treated from trichloroethene (TCE). This new material exhibits unique solid-state texture that rubbery polymer component are typically dispersed in lamellar structure matrix. Versus conventional PP or thermoplastic olefin (TPO), it provides excellent brittle-ductile (BD) transition as well as paintability. Also it is expected to have a significant impact on interior parts as requirements for material change to an emphasis on light weight, lower cost, more efficient finishing.

This paper presents a study on using rubber bushing as a sensor for the identification of forces transmitted onto the car body. The method starts from the idea that the transmission forces can be related to the deformation of the rubber bushing multiplied by its stiffness. Deformation of the rubber bushing is estimated from relative vibrations across the bushing. Simple theories are presented to deal with modeling of the rubber bushing and processing of the vibration mesurements on the link and car body to identify the transmission forces. Then, validity of the proposed approach is shown by applications to a suspension system under several driving conditions.

A new recycled material has been developed by using the scrap of tail lamp assembly, made of poly(methyl methacrylate) (PMMA) for the lens and acrylonitrile-butadiene-styrene terpolymer (ABS) for the housing. Lamp scrap was extruded in a twin-screw extruder, and mechanical properties of the scrap were compared with ABS, PMMA, and an ABS/PMMA (60/40) blend. The recycled material from 100% tail lamp scrap has similar modulus to the 60/40 blend, however, notched Izod impact strength and thermal resistance were lower than that of the blend, probably due to the presence of hot melt adhesive and silver paint. Scrap/virgin polymer mixtures showed improved thermal resistance and impact strength. The effects of composition and type of mixed polymer on mechanical properties were also investigated.

In recent years, high performance engines and the reduction in engine room due to aerodynamic styling has caused increases in engine room temperature. Because of this increasing temperature, the conventional natural rubber engine mount is now at the marginal point on its performance and durability. Several heat resistant materials have been considered for engine mount applications because of this reason. Polychloroprene rubber could be a strong candidate for engine mount application due to its balance of heat resistance, dynamic properties, and fatigue life. This paper will discuss the development of the technology, property characteristics and part performance simulations on the HYUNDAI BUSH TYPE COMPLEX ENGINE MOUNT (for 2.0L DOHC ENGINE). This type of mount requires higher creep resistance and fatigue life than those of other designs, such as block or simple shear type mounts. Early evaluations of polychloroprene mounts have shown some deficiencies in creep resistance.