Sökning: "Polyethylene pipes"
Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Polyethylene pipes.
1. Degradation of polyethylene pipes distributing chlorinated water : depletion of stabilizers, release of degraded products and polymer degradation
Sammanfattning : This thesis presents the study of antioxidants depletions in chlorinated media (10 ppm Cl2 - and ClO2 - aqueous media), polyethylene pipes degradations scenarios and migration of the degraded species to aqueous phase. Pressure testing on pipes and squalane testing with controlled pH aqueous media (6.8 ± 0. LÄS MER
2. Durability of District Heating Pipes
Sammanfattning : This thesis is focused on mechanical loads and moisture related problems with a potential to critically harm the functionality of pre-insulated district heating pipes and pipe joints. Directly buried pipeline bends are investigated with respect to limiting deformations from a thermally induced lateral displacement. LÄS MER
3. Deterioration of Polyethylene Exposed to Chlorinated Species in Aqueous Phases : Test Methods, Antioxidants Consumption and Polymer Degradation
Sammanfattning : This thesis presents a study of antioxidant depletion in water containing chlorinated species (water containing 10 ppm either Cl2 or ClO2, buffered to pH = 6.8), the degradation products in the aqueous phase, and polyethylene pipe degradation scenarios. LÄS MER
4. The influence of Morphology on the Transport and Mechanical Properties of Polyethylene
Sammanfattning : The sorption/desorption behaviour of n-hexane in high molarmass linear polyethylene (PE) and branched PEs with 0.39 and5.09 hexyl branches per 100 main chain C atoms andcrystallinities between 4 and 82% at 298 K has been studied.Crystal core contents determined by Raman spectroscopy werealways lower than those determined by density measurements. LÄS MER
5. Longterm performance of polyolefins in different environments including chlorinated water: antioxidant consumption and migration and polymer degradation
Sammanfattning : The long-term performance of stabilized polyolefins in different environments was studied with focus on antioxidant consumption and migration. Plaques of linear polyethylene (LPE) and branched polyethylene (BPE) were stabilized with Santonox® R (4,4'-Thiobis(6-tert-butyl-3-methylphenol)), Irganox® 1081 (2,2’-Thiobis(4-methyl-6-tertbutylphenol)), or Lowinox® 22M46 (2,2’-Methylenebis(6-tert-butyl-4-methylphenol)). LÄS MER