Ateva 1070 EVA Copolymer Resin,9% VA,2.8 MI,Wire & Cable Grade

Ateva 1070, a 9 wt% vinyl acetate ethylene-vinyl acetate copolymer with a melt flow index of 2.8 g/10 min under ISO 1133-1:2022 at 190 °C/2.16 kg and a density of 0.928 g/cm³ by ASTM D792, is incorporated into medium-voltage XLPE power cable conductor shield compounds at a polymer-phase replacement ratio of 20 wt% to 30 wt% relative to low-density polyethylene. The shield formulation combines the resin with 45 to 55 phr of conductive carbon black, 0.3 to 0.5 phr of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), and 1.8 to 2.3 phr dicumyl peroxide. Two-stage compounding is mandatory because the carbon black must be wetted into the polymer phase under shear while the peroxide must remain inert until the cable core reaches the continuous vulcanisation tube. A first pass is run on a co-rotating twin-screw compounder with 44:1 L/D, using side-fed carbon black at barrel temperatures 170 °C to 190 °C and an underwater pelletiser. A second pass introduces liquid dicumyl peroxide at 105 °C to 115 °C, with screw speed capped at 280 rpm to prevent viscous heating beyond 125 °C. Dicumyl peroxide displays a one-hour half-life at approximately 135 °C; exceeding 125 °C during the second pass reduces active peroxide content and shifts the cure curve. Carbon black pre-drying at 80 °C for 4 h is required when ambient relative humidity exceeds 60%, because moisture condenses at the carbon-black interface and disrupts the conductive network. The shielded copper conductor is extruded through a 60 mm 24:1 barrier screw crosshead at melt temperatures not above 125 °C and head pressures 180 bar to 260 bar. On a triple-head line, the melt is applied directly over the stranded or solid annealed copper before the insulation layer, and the three-layer dielectric system enters a steam cure tube at 200 °C and 2.0 MPa, with line speeds adjusted to produce hot-set elongation below 175% at 200 °C/0.2 MPa under IEC 60811-507. The resulting conductor shield is used in 6/10 kV to 20.8/36 kV XLPE-insulated power cables certified to IEC 60502-2:2014 or national equivalents such as DIN VDE 0276-620. This formulation must not be compounded with amine-based antioxidants or hindered amine light stabilisers because they scavenge free radicals during peroxide crosslinking and can depress final gel fraction.

Why Does the Sioplas Route Require Grafting Temperatures Above the Peroxide Half-Life Threshold?

Silane-mediated moisture crosslinking of low-voltage building conductors uses Ateva 1070 as a copper-adhesive co-resin in a graftable polyethylene backbone. The melt-phase grafting formulation consists of 70 wt% to 80 wt% linear low-density polyethylene, 20 wt% to 30 wt% Ateva 1070, 1.5 wt% to 2.0 wt% vinyltrimethoxysilane, and 0.05 wt% to 0.08 wt% dicumyl peroxide. Grafting is performed in a 45 mm single-screw extruder with 30:1 L/D and barrel profile 160 °C to 190 °C; residence time is held between 90 s and 120 s. The extruded single-core insulation is then catalysed with dibutyltin dilaurate at 0.05 wt% in a separate masterbatch or hot-water bath, and moisture curing proceeds at 70 °C/95% RH for 6 h to 10 h. The vinyl acetate carbonyl concentration of 9 wt% VA enhances adhesion to bare copper and tinned copper conductors, which is evaluated by stripping force and by 90° peel adhesion test per internal standards after ageing 7 days at 100 °C in air. This Sioplas route is incompatible with primary or secondary amine-containing additives because they react with both silanol condensation intermediates and residual peroxide fragments, shifting cure induction time and reducing crosslink density. Final crosslinked insulation for single-core building wire must exhibit tensile strength above 12.5 MPa and elongation above 200% before ageing, and hot set below 175% at 200 °C/0.2 MPa when tested to IEC 60811-507. The terminal products are halogen-free and crosslinkable single-core conductors such as 60227 IEC 02 or equivalent national types operating up to 90 °C conductor temperature.

Halogen-free flame-retardant sheathing for multi-core fixed-building cable under Construction Products Regulation uses Ateva 1070 as a viscosity and crystallinity modifier in a filled ethylene-vinyl acetate compound. A typical polymer phase contains 70 phr of 18 wt% VA EVA, 30 phr Ateva 1070, 10 phr LLDPE, 160 phr precipitated aluminium trihydrate, 10 phr zinc borate, 0.5 phr processing aid, 0.3 phr phenolic antioxidant, and 0.15 phr metal deactivator. The compound is mixed on a counter-rotating twin-screw extruder with 44:1 L/D and a 14-barrel profile, using water-cooled feed barrels and downstream barrel temperatures limited to 140 °C to prevent premature release of ATH water of crystallinity above 180 °C. Filler premixes are dried to moisture below 0.05 wt% in a dehumidified hopper at 80 °C for 6 h before side feeding. The addition of Ateva 1070 lowers compound melt viscosity sufficiently to permit strand die extrusion at 1.2 mm to 1.5 mm strand thickness, with die melt pressure 80 bar to 120 bar and screw torque at 78% of rated motor load. Fire performance is measured under EN 60332-1-2 for single-cable flame spread, EN 61034-2 for smoke transmittance, and EN 60754-2 for acid gas evolution. The terminal product is a flexible copper conductor with Cca-s1,d1,a1 or B2ca-s1,d1,a1 sheathing depending on total combustible content and heat release class. The formulation must avoid amine-based flame retardants because the compound is frequently peroxide-crosslinked in a dry cure line; residual amine species suppress the cure and shift the storage modulus trace in moving die rheometer measurements by 2 min to 5 min. The high ATH loading of 160 phr is not attainable with Ateva 1070 as the sole polymer resin; 9 wt% VA does not provide enough polar surface interaction to encapsulate ultrafine ATH particles, so an 18 wt% VA EVA or higher is mandatory.

In gas-injected physical foaming of high-density polyethylene for 75 Ω coaxial cable dielectric layers, Ateva 1070 is dosed at 10 wt% to 18 wt% of the total polymer melt as a secondary low-crystallinity phase. The acetate dipoles modify the elongational strain field during bubble growth and suppress cell coalescence in the tip-gap region of the extrusion die. The main resin is a high-density polyethylene with 0.943 g/cm³ to 0.954 g/cm³ density and 5.0 g/10 min to 8.0 g/10 min melt index. Nitrogen gas is injected at 280 bar to 320 bar into a 65 mm single-screw barrier extruder with 38:1 L/D and a static mixer before the die. Die temperature is maintained at 180 °C to 195 °C, and cooling is controlled to produce a closed-cell morphology with average cell size between 30 µm and 80 µm as measured by scanning electron microscopy. Adding Ateva 1070 above 18 wt% degrades capacitance stability because the loss tangent at 1 MHz rises and the characteristic impedance tolerance may exceed ±2 Ω. The resulting foam dielectric with skin layer is used in RG-6 CATV drop cable, RG-59 precision video cable, and satellite intermediate-frequency leads tested under IEC 61196-1-104 for return loss and IEC 61196-1-105 for attenuation. Published data for this specific Ateva 1070 foam configuration is limited; the stated range reflects industrial gas-foaming extrusion practice for low-VA EVA grades. Pre-drying of the pellet blend at 70 °C for 2 h is required when ambient RH exceeds 60%, since water dissolved in the melt produces irregular voids and high return loss in the 5 MHz to 1 GHz band.

When Ateva 1070 Replaces a Portion of LDPE in Heat-Shrink Cable Accessory Compounds

For electron-beam crosslinked heat-shrinkable tubing used in low-voltage cable joint encapsulation and busbar sleeving, Ateva 1070 is substituted into a polyolefin blend at 25 wt% to 40 wt% of the total polymer fraction, with 5 wt% to 8 wt% of a thermoplastic elastomer. The melt-blended formulation is extruded through a vacuum-calibrated die at 160 °C to 180 °C, then crosslinked with electron beam irradiation. The absorbed dose is held between 80 kGy and 120 kGy; gel fraction determined by ASTM D2765-16 reaches 50% to 65% in this window. Below 50% gel, the expanded tubing does not exhibit sufficient shape memory; above 65% gel, elongation at break falls below 400%, which limits expansion and longitudinal shrink-back. The crosslinked tube is reheated above the polyethylene crystallite melting point and expanded under compressed air at 2:1 to 3:1 drawdown. Tensile strength is evaluated per ASTM D2671, and longitudinal shrinkage is verified by UL 224 for extruded insulating tubing or by IEC 60684-3-216 for flexible heat-shrink sleeving. Ateva 1070 reduces the sealing force on copper and aluminium compression lugs because the vinyl acetate groups decrease crystallite size and lower the Vicat softening point relative to pure LDPE; this also shortens the adhesive activation window in dual-wall adhesive-lined tubing. The formulation must not be processed with acidic thermal stabilisers because vinyl acetate units are susceptible to acid-catalysed hydrolysis during extended ageing at 105 °C and 168 h. The finished products are used as joint sleeves in 0.6/1 kV low-voltage underground connections and as insulating sleeves in motor terminal insulation kits.

Solar Cable Sheathing Compliance Under EN 50618 Without Halogenated Synergists

In photovoltaic DC cable outer sheathing, Ateva 1070 is introduced at 15 wt% to 25 wt% of the total polymer fraction to balance crosslink density with high filler adhesion. The full formulation includes 50 phr to 60 phr of 18 wt% VA EVA, 20 phr to 25 phr Ateva 1070, 15 phr to 25 phr of metallocene linear low-density polyethylene, 150 phr to 180 phr precipitated aluminium trihydrate or a mixed ATH/MDH filler system, 8 phr to 12 phr zinc borate, 2.0 phr to 2.5 phr dicumyl peroxide, and 0.3 phr to 0.5 phr antioxidant. Mixing is performed on a counter-rotating twin-screw extruder with 48:1 L/D and melt temperature capped at 145 °C to preserve peroxide. The sheathing is applied via a 90 mm 24:1 crosshead extruder with a profiled die that maintains a thickness of 0.8 mm to 1.2 mm on 4 mm² to 6 mm² DC cable cores. Production-scale control is tied to EN 50618:2014 for the finished cable, IEC 62930:2017 for solar cables, and EN 60216-1:2013 or EN 60216-2:2005 for accelerated thermal endurance at 120 °C in air. The sheathed cable must pass vertical flame propagation under EN 60332-1-2, acid gas conductivity below 10 µS/mm under EN 60754-2, and smoke transmittance above 60% under EN 61034-2. The grade is not used as the sole polymer in solar sheathing because 9 wt% VA is insufficient to disperse 180 phr of hydrated filler without surface bloom; it functions as a co-resin that raises the melt elongation during sheathing and stabilises strand formation. The terminal product is a crosslinked halogen-free sheathed photovoltaic DC cable tagged H1Z2Z2-K under EN 50618 or PV1-F under 2Pfg 1169/08.2007.