Subject: Re: drying of HDPE
From: larryal@enter.net (Larry Alpert)
Date: 4 Nov 1996 01:32:59 GMT
In article <01bbc9e7$72857d80$9e469ace@Pengresin>,
engresin@webspan.net says...
>
>Can anyone please provide me with some information regarding the dryin
>high density polyethylene prior to its extrusion. I would like to kno
>drying is necessary, recommended, or just a waste of time. Also, are
>there any publications addressing this matter. Thank you.
Drying of HDPE is not needed, unless there is surface moiture present
(condensation from a cold wharehouse to a warm extrusion area can cause
this). It is not hydroscopic. In high volume applications, it can be preheated in
either a forced hot air system or dessicant drier mounted on the extruder throat
section, depending on the equipment you have.
The only time I have had problems is as mentioned above (shipment off of a
cold truck brought directly into the extrusion room).
--
---------------------------------------------------------
Lawrence Alpert FLUORTEK, INC. 610-559-9000 voice
Prod. Dev. Eng. 12 McFadden Rd. 610-559-1919 fax
larryal@enter.net Easton, PA 18045
Custom Medical Extrusions, Compounds, and Assemblies
Subject: Position for Composites Research Engineer/Scientist
From: Mark Battley
Date: Mon, 04 Nov 1996 16:33:22 +1200
Composites Research Engineer/Scientist
Industrial Research Limited is New Zealand's leading industrial and
engineering research institution with sites in Auckland, Wellington
and Christchurch. The company provides scientific and technological
research and development services to industry with an emphasis on the
manufacturing, natural products processing and energy sectors.
Activities include multi-year government funded research programmes,
joint R&D; projects with industry partners and industrial consultancy
and testing.
A position is available for a research engineer or scientist to join
its composites engineering research group at the company's Auckland
site. The current home of yachting's America's Cup, Auckland is New
Zealand's largest city and offers a mild climate with excellent
lifestyle opportunities.
The successful applicant will contribute to ongoing research
programmes, industry R&D; projects and consultancy services. This will
involve analytical and numerical modelling of composites, experimental
verification of composite material and structural behaviour, and
liaising with industrial clients.
Current composites related research projects include characterisation
of compressive and buckling failure mechanisms, modelling and
measurement of dynamic behaviour of composite marine vessels and
structures, application of acoustic emission monitoring as a
non-destructive evaluation method, and development of advanced design
methodologies for yacht spars.
Relevant postgraduate qualifications and/or appropriate research
experience, expertise in theoretical modelling of fibre reinforced
polymer composites, experience in finite element based structural
analysis and well developed written and oral communication skills are
desirable attributes.
Salary will be commensurate with qualifications and experience.
For further information contact Dr Mark Battley, ph +649 3034116, fax
+649 3070618 or email m.battley@irl.cri.nz.
Applications close Monday 25 November and should be sent with the
names of two referees to: Raewyn Steel, Industrial Research Limited,
PO Box 2225, Auckland, New Zealand.
Subject: Re: Need Good Cold Bonding Adhesives for Silicone
From:
Date: Mon, 4 Nov 1996 15:37:09 -0500
Brian,
We are currently applying for a patent to cover silicone bonding and
coatings on polyester materials, and a smililar process should work well
on PBT.
Secondly,
The primary focus of my current research is to apply silicone coatings to
stainless steel. I am currently studying 4 new processes we are
developing, and can discuss them on a limited basis with you.
Plasma pretreatments on stainless steel may provide the necessary surface
groups to acheive covalent bonding, but the stability is short lived, and
going from a plasma to a coating process is difficult. Using a silicone
plasma may also work, but it is our experience, when trying to attain
thicker coatings (1 micron and thicker) a plasma system is difficult to
acheive, and secondary coatings still do not bond well, because the
silicone coating is not functionalized.
Our research in functionalized surfaces for silicone coatings is
progressing well, and at least 3 of the 4 processes show much promise.
Please feel free to email your phone number, and I will call.
Chris W. Widenhouse, PhD
Biomedical Engineering Center
Dept. Materials Science and Engineering
University of Florida
cwiden@grove.ufl.edu
On Fri, 25 Oct 1996, Brian Land wrote:
> I need an adhesive that is appropriate for cold bonding the following
> interfaces.
>
>
> 1. silicone to stainless steel
> 2. silicone to plastic (PBT)
>
> The silicone is approx. Shore Durometer 30 A.
>
> I have already tried epoxy adhesives, acrylic adhesives, and
> cyanoacrylates but I have had no success. The silicone peels easily away
> from the adhesive even after curing.
>
> Does anyone out there know what adhesives will stick to silicone?
>
> Thanks,
> Brian
>
>