Sinopec-SVW C-l 1100dt/500f-High Resistance High Modulus (HSHM) PVA Filamento

The product designated Sinopec-SVW C-l 1100dt/500f High Strength High Modulus（HSHM） PVA Filament is a continuous poly(vinyl alcohol) multifilament yarn. The code 1100dt/500f identifies a nominal linear density of 1100 dtex and a filament count of 500, giving a nominal filament titre of 2.2 dtex per filament. The PVA generic name follows ISO 2076:2021, and linear density is determined in accordance with ISO 1889:2009. The HSHM designation denotes a high-orientation wet-spun or dry-jet wet-spun process followed by multi-stage drawing and thermal relaxation. In contrast to standard PVA filament used for apparel or sewing thread, the HSHM route increases crystalline orientation and reduces elongation at break while retaining the hydroxyl-rich surface that distinguishes PVA from polyester or polyolefin fibres. The yarn is supplied as a continuous filament, not as staple or short-cut fibre, so it can be used directly in load-bearing textile structures, braided reinforcements, filament winding, and cementitious textile laminates. Because the bundle contains 500 fine filaments, matrix impregnation and flexibility are improved relative to heavy monofilament constructions, but process tension and humidity control become controlling variables.

Structural Specifications and Test Designations

The following table lists representative HSHM PVA continuous-filament values for this construction. Lot-specific certificates of analysis govern, and the ranges are not a substitute for batch release testing.

For batch release, conditioned yarn should be sampled after 24 h exposure to 20±2 °C and 65±4 % RH per ISO 139:2005. The tensile values are measured on a constant-rate-of-extension tester with a 500 mm gauge length and 250 mm/min jaw speed, with pretension set at 0.5 cN/dtex. Lot-specific certificates may show narrower control limits, especially for elongation, which is sensitive to drawing temperature and relaxation speed. The density of PVA is lower than that of PET and glass, but higher than that of polypropylene and HMPE; this affects volumetric cost and weight in composite laminates.

What Distinguishes This 1100 dtex/500 f HSHM Filament from Conventional PVA and Other Synthetic Reinforcing Yarns?

Differentiation from other PVA grades and alternative synthetic filaments is based on tensile stiffness, surface chemistry, moisture interaction, and thermal service range. Conventional wet-spun PVA yarn can exhibit tenacity from 6.0–9.0 cN/dtex and initial modulus below 200 cN/dtex; the HSHM class shifts tenacity into the 11.5–13.5 cN/dtex band and initial modulus above 280 cN/dtex. The lower elongation at break, 6.0–8.0 %, means that the yarn reaches a higher proportion of its breaking load at small deformation, which is critical in stiff cementitious or structural matrices but reduces the toughness of the yarn itself compared with high-elongation PET. PVA has a moisture regain of approximately 3.0–5.0 % at standard textile conditions, whereas PET and HMPE absorb less than 1.0 %; this PVA hydrophilicity improves bond to aqueous polymer dispersions and cement paste, but it also means that wet tensile strength and modulus are lower than dry values and that package drying is required before processing in humid plants.

The data indicate that HSHM PVA occupies a position between standard industrial PET and high-performance fibres in tensile terms, while offering the lowest density among the high-modulus hydrophilic reinforcing yarns shown in the table. The hydroxyl-rich surface is a major differentiator in cementitious bonding, geotextile friction, and aqueous latex impregnation; however, it is also the reason why PVA grades cannot be considered drop-in replacements for PET in applications requiring low moisture uptake or for HMPE in submersion environments. The 500 f construction further influences handling: compared with heavy-decitex monofilaments, the multifilament yarn has a high specific surface area and requires a coating or sizing step to consolidate the bundle for weaving; compared with coarser multifilament industrial yarns, the smaller filament titre reduces bending stiffness.

When Continuous PVA Filament Is Processed on Warping, Braiding, and Textile-Reinforced Concrete Lines

Processing behaviour of the 1100 dtex/500 f HSHM yarn is controlled primarily by equilibrium moisture content, twist, and tension. PVA filaments become plasticised by water; at 65 % RH the equilibrium regain is 3.0–5.0 %, but in unventilated warehouses at relative humidity above 60 % RH, packages can reach 6.0–8.0 % surface moisture. In such conditions, the yarn should be conditioned in a dry-air cabinet at 40–50 °C for 12–24 h before warping. On sectional warping machines with electronic tension control, package tension should be maintained below 0.12 cN/dtex per yarn to avoid permanent elongation; this corresponds to 132 cN for the 1100 dtex bundle. Twist insertion on a two-for-one twister should be limited to 60–80 turns per metre for standard weaving preparation because higher twist can reduce tenacity efficiency and promote filament breaks when the yarn is dry. During sizing, low-add-on PVA or acrylic size systems at 8–12 % solids are commonly used; borate-based additives should be avoided or carefully evaluated because borate ions interact with PVA hydroxyls to form reversible di-diol crosslinks that increase yarn stiffness and cause flaking at the reed if the size film is not controlled. The sized yarn should not be overdried above 120 °C because localised oxidation and discoloration can begin near the drying cylinder surface even though the bulk yarn temperature appears lower.

Batch-to-batch variation is most often observed in elongation at break rather than tenacity. A campaign produced with a higher relaxation-zone temperature can shift elongation from 6.0 % toward 8.0 % while tenacity remains within the indicated band; this should be monitored when the filament is used in weaving because higher elongation reduces warp tension stability and can increase stop marks. Weaving plants running PVA HSHM filament on air-jet looms have reported that filamentation and filling insertion defects increase when package regain exceeds 6.0 %, especially if the yarn has been prestressed by high twist or by storage under compression. To limit these effects, the yarn should be handled with ceramic guides, package supports should avoid localised pressure, and conditioning should be completed before creeling. Static electricity is generally lower than with PET because the PVA surface is less hydrophobic, but in very dry winter conditions below 30 % RH, antistatic agents should be applied to high-speed warping equipment.

In textile-reinforced concrete and cementitious composite laminates, the 1100 dtex/500 f yarn is typically converted into a mesh or warp-knit grid with spacing from 10 mm to 25 mm. The yarn is coated with an epoxy or aqueous polymer dispersion to consolidate the bundle and improve stress transfer to inner filaments. The high modulus of HSHM PVA allows the textile to carry service loads at smaller crack widths than conventional PVA or PET textiles, but this advantage is available only if the textile is properly pre-tensioned during lamination and if the concrete cover provides sufficient anchorage length. PVA is compatible with ordinary Portland cement and has good resistance to calcium hydroxide, so long-term hydrolysis of the polymer backbone is not the limiting degradation mode under normal unsaturated conditions. However, because PVA absorbs water, saturated composite specimens should be evaluated under wet-conditioned tensile loading before permanent structural use. Published data for this specific configuration is limited in open composite test databases; therefore, project-specific testing according to ISO 527-4:2021 or the relevant national textile-concrete testing protocol should be performed to generate design values. In geotextile and soil reinforcement, the yarn can be used as a load-bearing warp in woven geogrid junctions, where its high modulus reduces junction elongation and its high surface energy improves interlock with granular fill compared with PET or PP.

Product safety status is polymer-level. Under REACH, poly(vinyl alcohol) is a polymer and therefore exempt from registration as a polymer substance; registration duties apply to monomers and any additives. Unmodified PVA is not expected to contain restricted heavy metals above the homogeneous-material limits in Directive 2011/65/EU Annex II, but final compliance depends on sizing, dyes, or coating materials. No specific FDA food-contact or medical-grade statement applies unless separately documented in the lot certification. Storage limitations include avoiding direct sunlight for prolonged periods because UV exposure can cause surface oxidation and loss of tensile elongation; packages should be stored in dry, ventilated conditions at 10–35 °C and below 60 % RH. The filament should not be used in continuous immersion at high temperature, such as hot-water circulating systems, without derating because PVA undergoes plasticisation and progressive strength loss above 60 °C in aqueous media. Alkaline resistance of PVA is high relative to PET, but strong oxidising acids and concentrated hydrogen peroxide can degrade the polymer; phosphoric acid at high temperatures is also incompatible. Processing plants should verify lot-specific certificate data for the exact C-l 1100dt/500f grade because production campaign differences in drawing ratio and relaxation can shift elongation and modulus within the HSHM class.