In hot-mix asphalt and warm-mix binder modification, CH1301-1HE is dispersed into a bituminous carrier that has been preheated to 165–175 °C before high-shear mixing. The grade designation places this material in the 1301-series SBS class, which is generally a linear styrene-butadiene-styrene block copolymer; downstream processors should verify bound styrene, diblock content, and oil extension on the certificate of analysis because these values govern maltene-phase distribution and the final glass transition of the modified binder. A typical starting addition of 3.5–5.5 wt% based on neat bitumen is elevated to 5.0–6.5 wt% for heavy-traffic intersections, bus lanes, and port pavements. The butadiene midblock swells in the maltene fraction, while the styrene endblocks remain associated below the polystyrene glass transition of approximately 95 °C, creating a physically crosslinked network that elevates the ring-and-ball softening point. Mixing is conducted in a rotor-stator high-shear mill at tip speeds of 18–25 m/s for 45–90 min; bulk temperature must not exceed 190–200 °C because the unsaturated midblock undergoes chain scission and gel formation at higher thermal loads. Dynamic shear rheometer frequency sweeps from 0.1–10 rad/s at 64 °C should show a transition from viscous to elastic response with increasing SBS content. After mixing, the compound is transferred to horizontal agitated storage tanks held at 150–165 °C. Storage stability is frequently corrected by adding elemental sulfur at 0.05–0.20 wt% of the bitumen; this creates sulfide bridges within the polybutadiene phase, stabilises the swollen network, and suppresses phase separation. Sulfur additions above 0.20 wt% can cause uncontrolled viscosity rise and gel particles. The modified binder is tested against ASTM D5 penetration, ASTM D36 softening point, ASTM D6084 elastic recovery, ASTM D2872 thin-film oven ageing, and AASHTO T315 dynamic shear rheometer grading. For performance-graded specification work, AASHTO T350 multiple stress creep recovery provides the non-recoverable creep compliance Jnr; values below 0.5 kPa⁻¹ at 3.2 kPa are required for extreme traffic, below 1.0 kPa⁻¹ for very heavy traffic, below 2.0 kPa⁻¹ for heavy traffic, and below 4.5 kPa⁻¹ for standard traffic. In production-scale asphalt plants, the main failure mode observed is two-phase separation in vertical storage tanks when recirculation is less than 0.5 tank volumes/h or when the mix temperature drops below 150 °C because the styrene domains re-associate and the swollen butadiene phase collapses. Maltene aromaticity differs by crude source; a feed with low aromatic content may require reduced SBS addition or longer mixing to avoid dry lumps. Published data for CH1301-1HE in specific high-viscosity bitumen feeds is limited; plant trials should include a storage stability column test at 163 °C for 72 h and rotational viscosity measurements at 135 °C using ASTM D4402 before full conversion.

What Processing Adjustments Prevent Over-Blowing of CH1301-1HE in Microcellular Sole Compounds?

Microcellular footwear compounds based on linear SBS require a defined oil-to-polystyrene ratio to control melt viscosity and cell nucleation. A start-point compound for CH1301-1HE can be built on 100 phr SBS, 10–30 phr general-purpose polystyrene, 20–50 phr naphthenic extender oil, 10–25 phr calcium carbonate, 2 phr zinc oxide, 1 phr stearic acid, 0.3–0.5 phr phenolic antioxidant, 1.5–3.5 phr modified azodicarbonamide, and 0.05–0.30 phr dicumyl peroxide if a partial crosslink is required. The polystyrene addition raises heat-distortion resistance of the expanded sole, but above 30 phr it narrows the foaming window and creates high die swell at the injection gate. Mixing is carried out in an internal mixer with a ram pressure sufficient to maintain fill factor 0.70–0.85; the drop temperature is held at 100–115 °C so that azodicarbonamide decomposition is delayed until the mould cavity. On a two-roll mill, the friction ratio is kept near 1.10–1.20 and the front roll temperature at 85–95 °C to prevent sticking without shearing the gel network. Injection moulding of the expanded sole uses barrel zones of 150 °C, 165 °C, and 175 °C, with nozzle temperature not exceeding 180 °C. The mould cavity is filled to 75–85% of its volume, allowing the blowing agent to expand the compound without producing sink marks or blown surface skins. Critical process limitations include the narrow decomposition range of the blowing agent and the thermal sensitivity of the SBS midblock; residence time above 190 °C should be limited to less than 2 min. In practice, the usable temperature window between complete blowing and thermal degradation is often narrower than ±5 °C in thick-section moulds. Finished soles are tested for Shore A hardness using DIN 53505, tensile strength and elongation at break using ASTM D412, trouser tear using ISO 34-1, and abrasion loss using DIN 53516. A medium-oil formulation typically falls in the range of Shore A 50–65, tensile strength 3.5–6.5 MPa, elongation 400–650%, and abrasion loss below 300 mm³, depending on filler grade and mould surface finish. Hygroscopic fillers should be pre-dried at 105 °C when ambient relative humidity exceeds 60%. Aromatic oil should be avoided because aromatic fractions partition into the polystyrene domains and reduce tensile strength at elevated service temperatures. Published data for this specific configuration is limited; the start-point formula should be adjusted with a Haake or Brabender torque rheometer at 170 °C to record gelation time before scaling to production.

When a hot-melt pressure-sensitive adhesive is formulated for tape and label stock, CH1301-1HE functions as the elastomeric network that balances tack, peel, and static shear. The adhesive is prepared in a heated sigma-blade or planetary mixer at 150–170 °C under a nitrogen blanket. A typical start-point formulation contains 100 phr CH1301-1HE, 80–130 phr of a C5 aliphatic or C5/C9 hydrogenated tackifier with a softening point of 90–110 °C, 20–50 phr naphthenic oil, and 1–2 phr of a hindered phenolic antioxidant. The tackifier-to-oil ratio is adjusted so that the Brookfield viscosity measured with ASTM D3236 at 160 °C falls between 5,000 and 30,000 mPa·s for slot-die coating. Higher tackifier loadings increase loop tack but reduce room-temperature static shear resistance; an excess of oil plasticises the polystyrene domains and lowers the upper service temperature. The adhesive is coated onto release liner or face stock at 150–170 °C using a slot die with a die gap of 0.15–0.30 mm; line speed is limited by cohesive strength development of the block copolymer network as it cools. Coated laminates are conditioned for 24 h at 23 ± 2 °C and 50 ± 5% RH before testing according to ASTM D6195 loop tack, ASTM D3330 peel adhesion, and ASTM D3654 static shear. A typical general-purpose tape target is loop tack 6–10 N/25 mm, 180° peel 5–8 N/25 mm, and static shear failure time above 24 h at 1 kg. Processors should monitor the adhesive melt temperature above 180 °C for prolonged periods; residence time beyond 4 h leads to viscosity drift, gel particle formation, and a brownish discolouration caused by thermo-oxidative attack on the polybutadiene unsaturation. Production-scale coating lines generally use a progressive cavity pump and heated hose assemblies with temperature variation less than ±3 °C; cold spots cause reticulation and streak defects. Published data for CH1301-1HE in specific high-solids hot-melt adhesive systems is limited; a laboratory paddle mixer trial with gel-free filtration through a 200 µm screen is recommended before continuous production.

Self-Adhesive Bituminous Sheet Compounds and Low-Temperature Flexural Integrity

Self-adhesive waterproofing membranes based on CH1301-1HE are compounded at 8–12 wt% into oxidised or distillation bitumen, together with 15–30 wt% limestone filler and 3–8 wt% naphthenic or paraffinic process oil. The SBS network shifts the low-temperature flexibility of the membrane; a membrane formulated with a 1301-series linear SBS is typically subjected to a mandrel bend test at -15 to -25 °C according to EN 1109. Mixing is performed in a heated planetary or horizontal ploughshare mixer at 170–190 °C for 60–120 min, followed by coating onto a polyester spunbond or glass fibre mat. The coating line uses a knife-over-roll or calender coater; compound viscosity must remain above 80 Pa·s at 180 °C to prevent strike-through into the reinforcement. Membrane performance is tested for tensile strength and elongation according to ASTM D5147, tear strength according to ASTM D4073, and dimensional stability at elevated temperature. In production, the most common failure is bridge formation on the coater caused by filler agglomeration when the filler is added too rapidly or when moisture content exceeds 0.3%. Processors should pre-dry limestone at 105 °C until moisture is below 0.1% and add the SBS as a pre-masterbatch to avoid undispersed elastomer particles. The membrane should be stored below 40 °C and away from direct sunlight because the unsaturated midblock can undergo slow oxidative embrittlement at exposed edges. Published data for CH1301-1HE in specific membrane compounds is limited; plant validation should include exudation testing of the finished roll at 50 °C for 7 days and a visual check for oil migration on the sanded or film surface.

Typically, melt-phase impact modification of polypropylene or polypropylene/polystyrene blends incorporates CH1301-1HE at 5–15 wt% using a co-rotating twin-screw extruder with L/D 32:1 to 40:1. The screw configuration includes forward conveying elements, kneading blocks, and a low-pressure devolatilisation vent. The SBS should be fed through the main throat only if the first barrel is cooled below 90 °C; otherwise a downstream side feeder into the melt stream reduces blocking at the feed throat. Melt temperature is maintained at 190–210 °C, and screw speed is set between 200 and 400 rpm depending on barrel diameter. The butadiene phase provides impact energy absorption, while the polystyrene endblocks preserve dimensional stability and reduce gross phase separation. The compounded blend is injection moulded into test plaques at 200–220 °C and conditioned for 40 h at 23 ± 2 °C before notched Izod impact testing according to ASTM D256. Typical development targets for a polypropylene homopolymer modified with 10 wt% SBS are a notched Izod impact increase of 2–5 times over the unmodified base, a tensile yield strength reduction of 10–20%, and a flexural modulus reduction of 15–25%. Tensile properties are measured using ASTM D638 and flexural properties using ASTM D790. Melt flow is measured with ASTM D1238 at 230 °C under 2.16 kg. Processors must not exceed 230 °C melt temperature because the polybutadiene segment begins thermo-oxidative chain scission, producing odour and surface streaking. If the base polypropylene contains peroxide residues or if barrel residence time extends beyond 3 min, gel particles may appear. Published data for CH1301-1HE in specific controlled-rheology PP grades is limited; a capillary rheometry sweep at 200 °C, 210 °C, and 220 °C should be performed to map viscosity before setting extruder speed.

If Solvent-Based Construction Sealants Require Cyclic Movement Accommodation Without Cohesive Failure

A solvent-based construction sealant containing CH1301-1HE is compounded in a vacuum dissolver at 20–30 °C to limit solvent evaporation and moisture ingress. The elastomer is dissolved in a solvent blend of toluene, cyclohexane, and methyl ethyl ketone at solids contents of 60–85 wt%. The selection of aromatic or aliphatic solvents determines the solubility parameter match with the polystyrene and polybutadiene segments; a mixed solvent system is frequently required to prevent gelation during storage. The sealant is thickened with fumed silica at 2–5 wt% and stabilised with 1 phr of a hindered amine light stabiliser and 0.5 phr of a phenolic antioxidant. At application, viscosity is adjusted to 1,000–5,000 mPa·s so that the material can be gun-applied without slumping on vertical substrates. After solvent release, the sealant develops a Shore A hardness of 20–40, a tensile strength of 0.5–2.0 MPa, and elongation at break above 600% when measured with ASTM D412. Cyclic movement capability is assessed according to ISO 11600, with the joint movement class determined by repeated extension and compression at -10 °C to 40 °C. Solvent-based SBS sealants are limited by their slow through-cure, particularly in joints deeper than 12 mm; application in thicker sections can cause skin-over followed by solvent entrapment and blistering. Avoid contact with ketone-dominated solvent systems above 40 °C; the combination can soften the polystyrene domains and produce a stringy, low-modulus film with poor recovery. Published data for CH1301-1HE in specific solvent-based construction sealants is limited; a laboratory storage test at 50 °C for 28 days should be conducted to measure viscosity drift, skin formation, and adhesion retention before field trials.

Extruded high-friction matting and sheet stock represent a further compounding route in which CH1301-1HE is combined with 20–40 phr naphthenic oil, 30–80 phr calcium carbonate or barytes, 5–15 phr pigment masterbatch, and 1–2 phr antioxidant. The dry blend is fed into a single-screw extruder with L/D 24:1 and a barrier screw; barrel temperatures rise from 130 °C to 170 °C, and the die is held at 150–165 °C. The molten sheet is calendered onto a textured roll to produce a slip-resistant surface. Tests include Shore A hardness using ASTM D2240, tear strength using ISO 34-1, and abrasion according to DIN 53516. Screw speed and feed rate must be balanced so that the melt temperature at the die lip does not exceed 185 °C; otherwise the sheet exhibits edge tearing and discolouration. Because the polybutadiene block contains residual unsaturation, the compound should not be stored near ozone-generating equipment or ultraviolet sources for extended periods. Published data for CH1301-1HE in high-friction sheet is limited; a short pilot extrusion trial with a screen pack of 100/80/60 mesh is recommended to identify pressure drop before commercial line operation.