The elimination of N-methyl-2-pyrrolidone as a cosolvent for controlling viscosity in the preparation of water-borne PU coatings by the prepolymer process is examined. Factors to be taken into account in the design of polymers without N-methyl-2-pyrrolidone are considered and the use of plasticisers as replacements for N-methyl-2-pyrrolidone as the prepolymer diluent is discussed. It is shown that PU dispersions produced with plasticisers instead of N-methyl-2-pyrrolidone can provide wood coatings with lower VOC demand and improved hardness.

Effects of five different paraffinic oils on the rheological, dynamic, and low temperature properties of three different ethylene propylene diene (EPDM) gum rubber compounds were evaluated. Rheological properties were evaluated using a capillary rheometer and Mooney measurements. Dynamic properties were examined using a viscoanalyser at a range of different frequencies. Low temperature properties utilised a Gehman torsion wire type of apparatus. Mooney viscosity depended strongly on the oil viscosity whilst both oil composition and ethylene content of the polymer affected melt flow properties. Low temperature behaviour depended on the glass transition temperature of the oil. 18 refs.

Information on mechanical properties of starch based materials was collated from the literature, and the information obtained was supported by experimentation using various published formulations containing wheat starch and polyvinyl alcohol or synthetic biodegradable polyesters as plasticisers. Preparations of films using an extrusion method, and testing techniques used were described. The existence of a master curve based on a simple starch, water and glycerol ternary system to which all wheat starch can be related is discussed. 58 refs.

The effects of plasticiser content and temperature on the migration of the plasticiser dioctyl phthalate (DOP) from poly(vinyl chloride) discs into well-stirred colza oil was investigated by weight loss and radioactive labelling studies. The application of a mathematical model to simulate DOP concentration profiles and to predict the kinetics of transfer into the oil is discussed. 16 refs.

The output of PVC in China was 5.03 million tons in 2004, an increase of 24.76% over the previous year, and the apparent consumption was 7.139 million tons, a rise of 12.3% over 2003. The output of plasticisers was 453,000 tons in 2004, a drop of 20.6% over 2003. As the rapid increase of crude oil prices prompted the price rise of plasticiser raw materials, some producers reduced operating rates to avoid the operating risks. The consumption decrease of plasticisers indicates that the consumption distribution of PVC is changing. The proportion of rigid PVC products has continued to increase, while the consumption proportion of flexible PVC products has gradually decreased due to partly being replaced by other products.

Crosslinked polymers are insoluble in all solvents, but they can be swollen to different extents, depending on their crosslinking degree, thereby resulting in gels. This article discusses secondary valence gels, covalent gels, hydrogels, sol-gel chemistry, smart gels and stimuli-responsive polymers. Applications include drug delivery, a biohybrid artificial pancreas and treatment of tumours. Molecular recognition, conversion of electrical energy to mechanical work and gels responsive to induction heating are also discussed.

A new generation of acrylic processing aids for polyvinyl chloride (PVC) which promote antisticking behaviour are discussed. The new developments in antisticking performance associated with appropriate rheological behaviour and optical criteria are made possible due to optimisation of the miscibility/compatability/migration ratio of the additive in the PVC matrix. The additive is particularly useful for processes involving high temperature or high shear, for high viscosity formulations, high sticking formulations and for full compliance with pharmaceutical and food applications. 9 refs.

New data for PVC is reviewed and presented with a focus on the use of models to simulate migration. Directive 2002/72/EC recognises that certain types of diffusion models can be used for certain polymers as a substitute for costly and time consuming migration testing. This article shows that PVC can be added to this category of polymer. 10 refs.

A demonstration is made of applicable pathways towards a balanced and holistic life-cycle (LC) related decision-support in procurement and purchasing for environmentally preferable solutions that are technically practicable and economically feasible. Polyvinyl chloride (PVC) is used as the example. The way of structuring available information leads to a discussion of the pros and cons of different solutions. LC assessments need to be taken at the application level rather than at the material level. For PVC the production of intermediates, stabilisers and plasticisers plays a major role in environmental impact. The role of recycling is addressed. 4 refs.