Hollow spheres for engineering thermoplastics

Hollow spheres for engineering thermoplastics

Additives for Polvmers March 1990 which test animals were fed a single dose of the material. Furthermore, the group says that tests carried out in t...

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Additives for Polvmers

March 1990

which test animals were fed a single dose of the material. Furthermore, the group says that tests carried out in the US in the late 1970s which showed that mice and rats tended to develop liver tumours were based on the animals being fed 12,006 parts per million DOP a day. Cefic says this is the equivalent to a man drinking about half a litre of DOP a day. The average human intake of plasticizers amounts to only 2 grammes a year, according to European and US studies. This mainly comes Tom traces of plasticizers migrating from food packaging. There is one application where DOP is positively beneficial: medical blood bags. In PVC bags made using this material the DOP migrates from the PVC into the blood, where it reduces the level of destruction of red cell walls compared to that which occurs in bags made of other materials, says Cefic. ’ As a consequence of these investigations, many official bodies and legislative authorities have concluded that plasticizers pose no significant hazard to man. ’

HALS as radiation stabilizers

Combinations of Irgafos 168 with Tinuvin 622 or Chimassorb 944 are particularly unique in that they are effective process, colour, and thermal stabilizers as well as W stabilizers. Such combinations are attractive candidates for polyolefm products that must undergo gamma sterilization. This article discusses recent investigations undertaken to evaluate the activity of HALS in such systems. Plast. Compound,

Hollow spheres for engineering thermoplastics

1989, 12, (Sept./Ott.),

69-70

A new class of 8 ,um, 1.1 g/ml hollow glass spheres from Potters Industries Inc. (affiliated to PQ Corp.), offers the potential of significant weight reduction when compounded into engineering polymers. The hollow spheres have low ionic leach and conductivity, suggesting use in electrical applications. They provide opacity and whitening when mixed into resin matrices, suggesting potential as extenders for Ti02s. Tensile, flexural, and impact properties of composites filled with the hollow glass spheres are similar to those of solid glass spheres, and early work shows significant benefits in properties when organosilane coupling agents are used. This article adapted from a paper presented at the SPI 44th Annual Composites Institute Conference, Dallas, 6-9 February 1989 describes their use in nylon 66, PET, PST, acetal, AE3S, polypropylene and high impact polystyrene. Plast. Compound.,

01990 Elsevier Science Publishers Ltd.

1989, 12, (Sept./Oct.j,

61-66

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