{"id":7210,"date":"2026-03-01T12:00:00","date_gmt":"2026-03-01T04:00:00","guid":{"rendered":"https:\/\/zetarmold.com\/?p=7210"},"modified":"2026-04-09T08:05:44","modified_gmt":"2026-04-09T00:05:44","slug":"formowanie-wtryskowe-ps","status":"publish","type":"post","link":"https:\/\/zetarmold.com\/pl\/formowanie-wtryskowe-ps\/","title":{"rendered":"R\u00f3\u017cnokolorowe granulki z tworzywa sztucznego u\u0142o\u017cone w stosy na bia\u0142ej powierzchni, wykorzystywane w procesach formowania wtryskowego."},"content":{"rendered":"
\n Kluczowe wnioski<\/strong>
\n \u2013 Polystyrene (PS) is an amorphous thermoplastic ideal for forma wtryskowa<\/a>ing, offering excellent clarity, dimensional stability, and fast cycle times of 15\u201330 seconds.
\n \u2013 PS injection molding operates at relatively low temperatures (180\u2013260\u00b0C melt, 20\u201350\u00b0C mold), making it energy-efficient compared to engineering plastics.
\n \u2013 General-purpose PS (GPPS) provides optical clarity up to 90% light transmission, while high-impact PS (HIPS) adds rubber-modified toughness for durable applications.
\n \u2013 Common PS applications include food packaging, disposable cutlery, electronics housings, and laboratory consumables \u2014 industries where cost and clarity matter most.\n<\/div>\n

What Is PS Injection Molding and Why Is It So Widely Used?<\/h2>\n

PS injection molding is a manufacturing process that melts polystyrene resin pellets and injects them into a precision mold cavity to produce finished plastic parts. Polystyrene is one of the most widely processed thermoplastics globally, with annual production exceeding 14 million metric tons. In our factory, we run PS parts daily \u2014 from clear food containers to electronics housings \u2014 because the material combines low cost ($1.00\u20131.50\/kg), easy processing, and excellent surface finish.<\/p>\n

Polystyrene belongs to the amorphous polymer<\/a>1<\/a><\/sup> family, which means it has no crystalline structure. This gives PS predictable shrinkage rates (0.3\u20130.6%), excellent dimensional accuracy, and no need for the extended cooling cycles that semi-crystalline materials demand. We\u2019ve found that PS consistently delivers \u00b10.1 mm tolerances on most part geometries without special tooling adjustments.<\/p>\n

Two main grades dominate PS injection molding:<\/p>\n\n\n\n\n\n\n\n\n\n
W\u0142asno\u015b\u0107<\/th>\nGPPS (General Purpose)<\/th>\nHIPS (High Impact)<\/th>\n<\/tr>\n<\/thead>\n
Przejrzysto\u015b\u0107<\/td>\nCrystal clear (90% light transmission)<\/td>\nOpaque<\/td>\n<\/tr>\n
Si\u0142a uderzenia<\/td>\nLow (15\u201320 J\/m)<\/td>\nModerate (60\u2013120 J\/m)<\/td>\n<\/tr>\n
Wytrzyma\u0142o\u015b\u0107 na rozci\u0105ganie<\/td>\n35\u201355 MPa<\/td>\n20\u201335 MPa<\/td>\n<\/tr>\n
Heat Resistance (HDT)<\/td>\n80\u201395\u00b0C<\/td>\n75\u201390\u00b0C<\/td>\n<\/tr>\n
Typical Use<\/td>\nClear packaging, optical parts<\/td>\nElectronics housings, appliances<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

<\/svg> \u201cPolystyrene requires high mold temperatures above 100\u00b0C for proper filling.\u201d<\/b>Fa\u0142sz<\/span><\/p>\n

PS is an amorphous polymer with a relatively low melt viscosity. Mold temperatures of 20\u201350\u00b0C are sufficient for most PS parts, which is one reason it\u2019s so energy-efficient to process.<\/p>\n<\/div>\n

\n

<\/svg> \u201cPS injection molding uses lower mold temperatures (20\u201350\u00b0C) than most engineering plastics.\u201d<\/b>Prawda<\/span><\/p>\n

Because PS is amorphous and has a glass transition temperature around 100\u00b0C, it solidifies quickly at low mold temperatures, enabling shorter cycle times and lower energy consumption.<\/p>\n<\/div>\n

What Are the Key Material Properties That Make PS Ideal for Injection Molding?<\/h2>\n

Polystyrene\u2019s key material properties \u2014 low melt viscosity, minimal shrinkage, and excellent flow characteristics \u2014 make it one of the easiest thermoplastics to injection mold. In our experience, PS fills thin-wall sections down to 0.5 mm with minimal pressure, something that materials like PC or POM struggle with at the same wall thickness.<\/p>\n

Here are the critical material properties we consider when selecting PS for a project:<\/p>\n\n\n\n\n\n\n\n\n\n\n
W\u0142asno\u015b\u0107<\/th>\nValue Range<\/th>\nWhy It Matters<\/th>\n<\/tr>\n<\/thead>\n
Wska\u017anik p\u0142yni\u0119cia (MFI)<\/td>\n2\u201330 g\/10min<\/td>\nHigher MFI = easier filling of complex geometries<\/td>\n<\/tr>\n
G\u0119sto\u015b\u0107<\/td>\n1.04\u20131.06 g\/cm\u00b3<\/td>\nLightweight parts, lower material cost per volume<\/td>\n<\/tr>\n
Wsp\u00f3\u0142czynnik skurczu<\/td>\n0.3\u20130.6%<\/td>\nPredictable dimensions, tight tolerances achievable<\/td>\n<\/tr>\n
Temperatura mi\u0119knienia Vicat<\/td>\n85\u2013105\u00b0C<\/td>\nDefines maximum service temperature<\/td>\n<\/tr>\n
Wytrzyma\u0142o\u015b\u0107 dielektryczna<\/td>\n20\u201328 kV\/mm<\/td>\nGood electrical insulation for electronics<\/td>\n<\/tr>\n
Water Absorption (24h)<\/td>\n0.03\u20130.10%<\/td>\nMinimal drying needed before processing<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

One practical advantage we appreciate: PS has very low moisture absorption, typically under 0.1%. This means we can often skip the pre-drying step that\u2019s mandatory for materials like nylon or PET. For GPPS, we go straight from the bag to the hopper in most cases. HIPS may benefit from 1\u20132 hours at 70\u201380\u00b0C if the material has been stored in humid conditions, but it\u2019s rarely critical.<\/p>\n

How Does the PS Injection Molding Process Work Step by Step?<\/h2>\n

The PS injection molding process follows the standard thermoplastic injection cycle \u2014 plastication, injection, packing, cooling, and ejection \u2014 but with parameters optimized for polystyrene\u2019s low viscosity and fast solidification. A typical cycle runs 15\u201330 seconds, which is 20\u201340% faster than comparable parts in ABS or PC.<\/p>\n

\"Plastic
Plastic resin pellets used in injection molding<\/figcaption><\/figure>\n

Here\u2019s how we run PS in our factory:<\/p>\n

Zmniejsz ci\u015bnienie docisku, zwi\u0119ksz temperatur\u0119 formy do 40\u201350\u00b0C, dodaj k\u0105ty odci\u0105gu \u22651,5\u00b0<\/strong> Load PS pellets into the hopper. For GPPS, no drying is usually required. For HIPS, dry at 70\u201380\u00b0C for 1\u20132 hours if needed.<\/p>\n

Step 2: Plastication.<\/strong> The screw rotates to melt PS at 180\u2013260\u00b0C. We use a general-purpose screw with a 2.0\u20132.5:1 compression ratio. PS melts easily and doesn\u2019t require high temperatura topnienia<\/a>2<\/a><\/sup> precision \u2014 a \u00b15\u00b0C variation is acceptable.<\/p>\n

Step 3: Injection.<\/strong> The screw pushes forward at 30\u201380 mm\/s injection speed, filling the cavity at 40\u2013100 MPa pressure. PS flows readily, so we keep injection speed moderate to avoid jetting marks on the surface.<\/p>\n

Step 4: Packing and Holding.<\/strong> We apply holding pressure at 40\u201360% of injection pressure for 3\u20138 seconds to compensate for shrinkage. Since PS has low shrinkage (0.3\u20130.6%), packing time is relatively short.<\/p>\n

Step 5: Cooling.<\/strong> Parts cool in the mold at 20\u201350\u00b0C for 8\u201320 seconds. PS solidifies quickly as an amorphous material \u2014 no crystallization time needed.<\/p>\n

Step 6: Ejection.<\/strong> Mold opens and ejector pins push the part out. PS is rigid and can be brittle (especially GPPS), so we use sufficient ejector pins to distribute force evenly and avoid cracking.<\/p>\n

What Processing Parameters Are Critical for PS Injection Molding Quality?<\/h2>\n

The critical processing parameters for PS injection molding are melt temperature, injection speed, and cooling time. Getting these three right determines whether you produce crystal-clear GPPS parts or end up with haze, stress marks, and brittle failures. We\u2019ve optimized these parameters across hundreds of PS projects, and the table below reflects our proven settings.<\/p>\n

\"Injection
Injection molding machine in production<\/figcaption><\/figure>\n\n\n\n\n\n\n\n\n\n\n\n\n
Parametr<\/th>\nGPPS Range<\/th>\nHIPS Range<\/th>\nUwagi<\/th>\n<\/tr>\n<\/thead>\n
Temperatura topnienia<\/td>\n180\u2013240\u00b0C<\/td>\n200\u2013260\u00b0C<\/td>\nHigher temp improves clarity for GPPS<\/td>\n<\/tr>\n
Temperatura formy<\/td>\n20\u201340\u00b0C<\/td>\n30\u201350\u00b0C<\/td>\nLower temp = faster cycle, higher temp = better surface<\/td>\n<\/tr>\n
Ci\u015bnienie wtrysku<\/td>\n40\u201380 MPa<\/td>\n50\u2013100 MPa<\/td>\nHIPS needs slightly more pressure<\/td>\n<\/tr>\n
Pr\u0119dko\u015b\u0107 wtrysku<\/td>\nMedium (30\u201360 mm\/s)<\/td>\nMedium-fast (40\u201380 mm\/s)<\/td>\nToo fast causes jetting; too slow causes flow marks<\/td>\n<\/tr>\n
Ci\u015bnienie trzymania<\/td>\n30\u201350 MPa<\/td>\n35\u201360 MPa<\/td>\n40\u201360% of injection pressure<\/td>\n<\/tr>\n
Czas utrzymywania<\/td>\n3\u20136 seconds<\/td>\n4\u20138 seconds<\/td>\nUntil gate freeze-off<\/td>\n<\/tr>\n
Czas ch\u0142odzenia<\/td>\n8\u201315 seconds<\/td>\n10\u201320 seconds<\/td>\nDepends on wall thickness<\/td>\n<\/tr>\n
Ci\u015bnienie wsteczne<\/td>\n3\u201310 MPa<\/td>\n5\u201315 MPa<\/td>\nEnsures uniform melt homogeneity<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A key lesson we\u2019ve learned: for GPPS clarity parts, keep the melt temperature at the higher end (220\u2013240\u00b0C) and injection speed moderate. High speed creates shear-induced haze that ruins optical transparency. For HIPS parts where impact resistance matters more than appearance, we push the melt temperature to 240\u2013260\u00b0C to fully disperse the rubber phase.<\/p>\n

\n

<\/svg> \u201cPS requires extensive drying (4+ hours) before injection molding, just like nylon.\u201d<\/b>Fa\u0142sz<\/span><\/p>\n

Polystyrene absorbs very little moisture (0.03\u20130.10% in 24 hours). GPPS can typically be processed without drying, and HIPS only needs 1\u20132 hours at 70\u201380\u00b0C in humid conditions. This is far less demanding than nylon, which requires 4\u20136 hours of drying.<\/p>\n<\/div>\n

\n

<\/svg> \u201cPS has one of the lowest moisture sensitivity levels among common injection molding plastics.\u201d<\/b>Prawda<\/span><\/p>\n

With water absorption under 0.1%, PS is far less moisture-sensitive than nylon (1.5\u20132.5%), PET (0.3%), or even ABS (0.2\u20130.4%). This simplifies material handling and reduces pre-processing time and cost.<\/p>\n<\/div>\n

What Are Common Defects in PS Injection Molding and How Can You Prevent Them?<\/h2>\n

The most common defects in PS injection molding are cracking\/brittleness, flow marks, and silver streaks \u2014 all directly linked to PS\u2019s amorphous, rigid molecular structure. In our production, we\u2019ve developed specific countermeasures for each defect that reduce reject rates below 1%.<\/p>\n

\"Mold
Precision mold tooling inspection and measurement<\/figcaption><\/figure>\n\n\n\n\n\n\n\n\n\n\n\n
Wada<\/th>\nRoot Cause<\/th>\nRozwi\u0105zanie<\/th>\n<\/tr>\n<\/thead>\n
Cracking \/ Brittleness<\/td>\nExcessive internal stress, over-packing<\/td>\nReduce holding pressure, increase mold temp to 40\u201350\u00b0C, add draft angles \u22651.5\u00b0<\/td>\n<\/tr>\n
Srebrne smugi<\/td>\nPS kosztuje o 30\u201340% mniej ni\u017c ABS i przetwarza si\u0119 szybciej przy ni\u017cszym zu\u017cyciu energii. Jednak ABS oferuje 5\u201310 razy wi\u0119ksz\u0105 wytrzyma\u0142o\u015b\u0107 na uderzenia i lepsz\u0105 odporno\u015b\u0107 na ciep\u0142o (95\u2013110\u00b0C vs 80\u201395\u00b0C). Wybierz PS, gdy liczy si\u0119 koszt i przejrzysto\u015b\u0107; wybierz ABS, gdy cz\u0119\u015bci musz\u0105 wytrzyma\u0107 uderzenia, wy\u017csze temperatury lub kontakt z chemikaliami.<\/td>\nDry material if needed, reduce melt temp, check for contamination<\/td>\n<\/tr>\n
Znaki przep\u0142ywu<\/td>\nCold material, slow injection<\/td>\nIncrease melt temp by 10\u201315\u00b0C, optimize injection speed profile<\/td>\n<\/tr>\n
Haze (GPPS)<\/td>\nShear-induced crystallites, contamination<\/td>\nReduce injection speed, clean barrel thoroughly, use virgin material<\/td>\n<\/tr>\n
Wypaczenie<\/td>\nUneven cooling, asymmetric wall thickness<\/td>\nBalance cooling channels, maintain uniform wall thickness \u00b110%<\/td>\n<\/tr>\n
Znaki zlewu<\/td>\nThick sections, insufficient packing<\/td>\nCore out thick areas, increase holding pressure\/time<\/td>\n<\/tr>\n
Jetting<\/td>\nHigh-speed entry through small gate<\/td>\nEnlarge gate, reduce initial injection speed, use fan gate<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

One critical issue unique to PS: stress cracking when exposed to certain chemicals. We\u2019ve seen GPPS parts crack spontaneously after contact with adhesives, cleaning solvents, or even certain printing inks. Always test chemical compatibility before specifying PS for parts that will be bonded, painted, or exposed to solvents in service.<\/p>\n

Where Is PS Injection Molding Used in Real-World Applications?<\/h2>\n

PS injection molding is used extensively in food packaging, consumer electronics, medical\/laboratory products, and household goods \u2014 industries where cost efficiency, clarity, and ease of processing outweigh the need for high impact or heat resistance. We produce PS parts for clients across all these sectors, and the material\u2019s versatility continues to surprise us.<\/p>\n

\"Prototype
Batch of injection molded plastic parts<\/figcaption><\/figure>\n

Food Packaging (GPPS & HIPS):<\/strong> Clear clamshell containers, yogurt cups, disposable cutlery, and deli trays. GPPS provides the transparency consumers expect, while HIPS handles applications needing more durability. PS is FDA-compliant for food contact.<\/p>\n

Consumer Electronics (HIPS):<\/strong> TV housings, remote control cases, printer cartridges, and appliance panels. HIPS offers good impact resistance, easy painting\/printing, and low cost for high-volume consumer products.<\/p>\n

Medical and Laboratory (GPPS):<\/strong> Petri dishes, test tubes, pipette tips, and diagnostic device housings. GPPS\u2019s optical clarity and gamma-sterilization compatibility make it standard in lab consumables.<\/p>\n

Household Products:<\/strong> CD\/DVD cases, picture frames, coat hangers, and storage organizers. PS molds easily into detailed shapes with excellent surface finish at minimal cost.<\/p>\n

Toys and Models:<\/strong> Model kits, building blocks (non-structural), and disposable toys. PS accepts colorants well and produces sharp detail in thin-wall parts.<\/p>\n

How Does Mold Design Affect PS Injection Molding Quality?<\/h2>\n

Mold design directly determines PS part quality in three critical ways: gate placement controls flow pattern and surface appearance, cooling layout affects cycle time and warpage, and draft angles prevent cracking during ejection. Since PS is more brittle than ABS or PP, mold design errors that might be tolerable with tougher materials become reject-causing problems with polystyrene.<\/p>\n

\"Quality
Quality inspection of injection molded plastic parts<\/figcaption><\/figure>\n

Konstrukcja bramy:<\/strong> We recommend fan gates or submarine gates for PS parts. Pin gates work for small parts but can cause gate stress<\/a>3<\/a><\/sup> concentrations that lead to cracking. Gate diameter should be 60\u201380% of wall thickness for GPPS, and slightly larger for HIPS.<\/p>\n

Cooling Layout:<\/strong> Uniform cooling is critical because PS warps easily with temperature differentials. We maintain cooling channel spacing at 1.5\u20132\u00d7 the channel diameter from the cavity surface, with water temperature kept at 20\u201340\u00b0C. Conformal cooling helps significantly for complex geometries.<\/p>\n

Draft Angles:<\/strong> PS requires minimum 1\u20132\u00b0 draft \u2014 more than PP (0.5\u20131\u00b0) \u2014 because its rigidity and brittleness make it prone to cracking if forced off the core. For textured surfaces, add 1\u00b0 per 0.025 mm texture depth.<\/p>\n

Grubo\u015b\u0107 \u015bcianki:<\/strong> Maintain uniform walls between 1.0\u20133.0 mm. PS can fill down to 0.5 mm in short-flow applications, but walls below 1.0 mm increase brittleness risk. Thickness variation should stay within \u00b110% to prevent wypaczenie<\/a>4<\/a><\/sup>.<\/p>\n

Ejection System:<\/strong> Use more ejector pins than you would for PP or PE. We typically space ejectors no more than 50 mm apart for PS parts, and use blade ejectors for long edges to distribute force and prevent stress fractures.<\/p>\n

Frequently Asked Questions About PS Injection Molding<\/h2>\n

What is the difference between GPPS and HIPS for injection molding?<\/strong>
\nGPPS (General Purpose Polystyrene) is transparent, rigid, and brittle with 90% light transmission, ideal for clear packaging and optical applications. HIPS (High Impact Polystyrene) is opaque and rubber-modified, offering 3\u20136\u00d7 higher impact strength (60\u2013120 J\/m vs 15\u201320 J\/m), making it suitable for electronics housings and durable consumer products.<\/p>\n

Can PS injection molded parts be recycled?<\/strong>
\nYes, PS is fully recyclable under resin identification code #6. Both GPPS and HIPS can be reground and reprocessed. In our factory, we routinely blend up to 20\u201330% regrind with virgin PS without significant property loss. However, municipal recycling programs for PS vary by region, so check local regulations.<\/p>\n

What is the typical cycle time for PS injection molding?<\/strong>
\nTypical PS cycle times range from 15\u201330 seconds for standard parts with 1.5\u20132.5 mm wall thickness. This is 20\u201340% faster than ABS or PC parts of similar geometry, primarily because PS solidifies rapidly and needs lower mold temperatures. Thin-wall packaging parts can cycle as fast as 8\u201312 seconds.<\/p>\n

Is PS safe for food contact applications?<\/strong>
\nYes, both GPPS and HIPS grades are available in FDA-compliant and EU 10\/2011-compliant formulations for food contact. PS is widely used for yogurt cups, deli containers, and disposable cutlery. Always specify food-grade resin from your supplier and ensure processing temperatures stay below 280\u00b0C to avoid thermal degradation.<\/p>\n

How does PS compare to ABS for injection molding?<\/strong>
\nPS costs 30\u201340% less than ABS and processes faster with lower energy consumption. However, ABS offers 5\u201310\u00d7 higher impact strength and better heat resistance (95\u2013110\u00b0C vs 80\u201395\u00b0C). Choose PS when cost and clarity matter most; choose ABS when parts need to withstand impacts, higher temperatures, or chemical exposure.<\/p>\n

Wysokotechnologiczna fabryka formowania wtryskowego z zautomatyzowanymi liniami produkcyjnymi<\/strong>
\nPost-molding cracking in PS is typically caused by residual napr\u0119\u017cenie wewn\u0119trzne<\/a>5<\/a><\/sup> from over-packing, excessive injection speed, or insufficient draft angles. Environmental stress cracking from contact with solvents, adhesives, or printing chemicals is another common cause. Reduce holding pressure, increase mold temperature, and test chemical compatibility to prevent this.<\/p>\n

\"Injection
Various injection molded plastic parts<\/figcaption><\/figure>\n

Podsumowanie<\/h2>\n

PS injection molding remains one of the most cost-effective and versatile manufacturing processes for producing clear, dimensionally stable plastic parts at high volumes. With melt temperatures of 180\u2013260\u00b0C, mold temperatures of 20\u201350\u00b0C, and cycle times as short as 15 seconds, polystyrene is one of the easiest thermoplastics to process. The two main grades \u2014 GPPS for optical clarity and HIPS for impact resistance \u2014 cover applications from food packaging to electronics housings. Success with PS depends on controlling injection speed to avoid haze and stress marks, designing molds with adequate draft and ejection, and being mindful of the material’s brittleness and chemical sensitivity. At Zetar, we’ve refined our PS molding processes across hundreds of projects, and we’re always ready to help you find the right approach for your next polystyrene application. See our Injection Molding Complete Guide<\/strong> for a comprehensive overview. See our Injection Molding Complete Guide<\/a> for a comprehensive overview.<\/p>\n

\n
\n
    \n
  1. \n

    Amorphous polymer refers to a plastic whose molecular chains lack long-range crystalline order, resulting in transparency, isotropic shrinkage, and a distinct glass transition temperature rather than a sharp melting point.\u00a0↩<\/a><\/p>\n<\/li>\n

  2. \n

    Melt temperature is the temperature at which the polymer is fully molten and fluid enough for injection, measured at the nozzle tip. It directly affects flow behavior, molecular orientation, and potential thermal degradation.\u00a0↩<\/a><\/p>\n<\/li>\n

  3. \n

    Gate stress is the localized residual stress concentration at the gate area of an injection molded part, caused by high shear rates and rapid cooling as material enters the cavity through the gate.\u00a0↩<\/a><\/p>\n<\/li>\n

  4. \n

    Warpage is the dimensional distortion of an injection molded part from its intended shape, caused by non-uniform shrinkage due to uneven cooling, inconsistent wall thickness, or molecular orientation differences.\u00a0↩<\/a><\/p>\n<\/li>\n

  5. \n

    Internal stress (residual stress) is the stress locked within a molded part after cooling, resulting from molecular orientation during flow and differential cooling rates. It can cause delayed cracking, warpage, or reduced chemical resistance.\u00a0↩<\/a><\/p>\n<\/li>\n<\/ol>\n<\/div>\n

    \n

    Need a Quote for Your Injection Molding Project?<\/strong><\/p>\n

    Get competitive pricing, DFM feedback, and production timeline from ZetarMold’s engineering team.<\/p>\n

    Request a Free Quote \u2192<\/a><\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"

    Kluczowe wnioski \u2013 Polistyren (PS) to amorficzny termoplast idealny do formowania wtryskowego, oferuj\u0105cy doskona\u0142\u0105 przejrzysto\u015b\u0107, stabilno\u015b\u0107 wymiarow\u0105 i kr\u00f3tkie czasy cyklu wynosz\u0105ce 15\u201330 sekund. \u2013 Formowanie wtryskowe PS odbywa si\u0119 przy stosunkowo niskich temperaturach (180\u2013260\u00b0C stop, 20\u201350\u00b0C forma), co czyni je energooszcz\u0119dnym w por\u00f3wnaniu z tworzywami konstrukcyjnymi. \u2013 Polistyren og\u00f3lnego przeznaczenia (GPPS) zapewnia przejrzysto\u015b\u0107 optyczn\u0105 do 90% [\u2026]<\/p>","protected":false},"author":1,"featured_media":53140,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"PS Injection Molding: Complete Polystyrene Molding Guide","_seopress_titles_desc":"Learn PS injection molding: GPPS vs HIPS properties, processing parameters, mold design tips, and real factory insights from ZetarMold.","_seopress_robots_index":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[42,45],"tags":[165,164,89,193,157],"meta_box":{"post-to-quiz_to":[]},"_links":{"self":[{"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/posts\/7210"}],"collection":[{"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/comments?post=7210"}],"version-history":[{"count":0,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/posts\/7210\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/media\/53140"}],"wp:attachment":[{"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/media?parent=7210"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/categories?post=7210"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zetarmold.com\/pl\/wp-json\/wp\/v2\/tags?post=7210"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}